Question 71: Answer shall be D as in all other we have overlapping IP Range.

Question 16: As per Oracle they do not have any 2 regions which are located within a range of 300 miles from each other and each region is in different country.
Mostly we shall go with A as it speaks about different AD in same domain.

Question 1: Answer should be C

Question 93: https://medium.com/@tigerbabu/oracle-cloud-infrastructure-associate-architect-notes-
4495b25b24a4

Above link also not showing anything which can proof option D is correct.

Question 92: Option C and D are correct option, for detail please login to OCI console and click on create instance button , while selecting image, there are 6 options are available (Platform Image, Partners Image , Image OCID, Boot volume, Custom image)

Question 89: As requirement is to access public cloud (object storage), so Public peering should be the correct option, and with Fastconnect BGP routs suits this requirement, private peering again add more complexity as it will require DRG which should associate with VCN , then with service gateway the same can achieve which should not be a good architecture so option D should be the correct option.

Question 87: Option B should be the correct one, Option C should not be correct as database should not be accessible through internet.

Question 83: Option D should be the correct option, as by default no access is granted in OCI, and here to use Instance principle , matching rule and dynamic group needs to be defined.

Question 81: https://docs.cloud.oracle.com/iaas/Content/File/Concepts/filestorageoverview.htm

As per above doc, below is the statement:
"Oracle Cloud Infrastructure users require resource permissions to create, delete, and manage resources. Without the appropriate IAM permissions, you cannot export a file system through a mount target. Until a file system has been exported, Compute instances cannot mount it. "
In a question , already followed the steps to mount the shared file system on your Oracle Linux virtual Instance, however issue is still unable to access the shared file system from your Linux instance..
IAM policy is ok and that is why able to follow the step to mount it, however file system is not accessible due to ports are not open through security list , so correct option should be A.

Question 69: As the requirement are:
1. should be far away from home site
2. distance should be more than 300 miles

To meet the above requirement, two separate regions would be the better solution, and VCNs on different region can be connected with remote peering.

Question 66: https://docs.cloud.oracle.com/iaas/Content/Balance/Concepts/balanceoverview.htm
As Web servers are placed in different ADs, so - 3 Subnet
For load balancer , i 2 subnets are required {one is primary and one is standby} in two different ADs, in case of regional subnet only one subnet will be required, however here the question is related with AD specific subnets so total required subnets will be 5.

Question 59: https://blogs.oracle.com/cloud-infrastructure/introducing-volume-groups:-enabling-coordinated-backups-and-clones-for-application-protection-and-lifecycle-management

Question 59: Boot volume or Block volume, both are block volume only and as per FAQ, below question is showing deatil about volume backup applicable for both types of backup, so option B should be the correct option.
What is a volume group backup? How does it work?
A coordinated point-in-time crash consistent backup of the entire set of volumes that are in a volume group. This operation creates a volume group backup. There is no impact to the source volume group and volumes during the backup process.

Volume group backups are replicated across all Availability Domains within the region where the source volume group resides. A volume group backup can then be used to create a new volume group to any Availability Domain within the region the backup resides, by restoring all the volumes data that are in the volume group.

Question 55: Correct answer should be B, https://cloud.oracle.com/storage/data-transfer-appliance/faq

Question 55: As per Data transfer FAQ, option B should be the correct answer.

Question 52: Option B cannot be the correct option, as Public and Private subnets can be in same AD for a given VCN.
Option A and D should be correct answers

Question 48: Option A should be the correct option as per doc https://cloud.oracle.com/storage/file-storage/faq

Description of NFS export options :NFS export options apply access control to network security lists and NFS version 3 UNIX authentication. You can use NFS export options to limit access levels by IP addresses or CIDR blocks that connect to multiple file systems through exports of an associated mount target. As a result, access can be restricted so that each client’s file system is completely inaccessible and invisible to the others, which provides security for multitenant or managed-hosted environments. Moreover, you can set permissions for read-only, read/write, or root-squash for your file systems.

Question 46: https://dyn.com/blog/internet-intelligence-now-available-in-the-oracle-cloud-infrastructure-console/

Question 41: Option A cannot be correct , as per doc https://docs.cloud.oracle.com/iaas/Content/Network/Tasks/managingDRGs.htm.
One VCN can have only one DRG attached

B,C,E should be the correct option, D should not be the accurate answer as question is about high availability but not only to setup hybrid connection.
Below doc describe why B and C are correct.
https://cloud.oracle.com/iaas/whitepapers/best-practices-deploying-ha-architecture-oci.pdf

Question 39: As per https://cloud.oracle.com/en_US/bare-metal-network/vcn/faq, below question clearly describe Service gateway is regional service, so option B cannot be the correct option.
Correct option should be A, as route table should have rule to send object storage related traffic through service gateway instead of NAT or Internet Gateway

Below question from FAQ:
Can I configure the service gateway to access services running in a different region?

--No, the service gateway is regional and can access only services running in the same region.

Question 38: D option should be the correct one as per https://cloud.oracle.com/storage/file-storage/faq ,
question :How do I manage security and access control for my file systems?
-- NFS version 3 manages security with standard UNIX-style read/write/execute permissions, based on user and group IDs. We verify the UNIX security model for authentication each time files are accessed.

Question 34: OPtion A clearly showing "Instance Subnet Route table", this option is more accurate then option B.

Option D: As ping has been tried from compute instance on OCI, so traffic should be allowed for outbound connection , so egrass should be the correct option for ICMP traffic.

Question 29: Answer should be B and C, the reason of C is , instances are not able to access internet those are in public subnet, so egrass rule needs to be checked.

Question 25: Block Volume and Instance are Availability domain specific, so it is not possible to attach block volume of different AD to instance running on different AD, so answer B & C are correct answers , C is correct as per FAQ "https://cloud.oracle.com/database/faq"

Question 17: DBCS provides options like RAC and data guard for high availability, which would be manual process if use Oracle database in compute instance, so here answer should be A, as DBCS service provides feature to use RAC by selection just node option.

Question 16: Correct answer should be D, as requirement is the DR site should be at least 300 miles far from home OCI region.

Question 15: Answer should be B as there is option available on same place as describing in point B

Question 14: Answer should be A & D, as DRG is for something connect without using internet, and here Instances required to connect to Internet those are in public subnet, so main cause should be egrass rule in security list or Route table is not set to Internet Gateway.