Your company has set up the AWS Managed Microsoft AD directory. There are on-premises nodes that will be using the AWS Managed Microsoft AD directory for authentication. You need to ensure that all traffic is encrypted in transit. How can you achieve this in the most IDEAL manner?

Answer options:

A.Make use of KMS Keys to encrypt the traffic.
B.Enable LDAP over SSL.
C.Enable LDAP over HTTPS.
D.Enable Server-side encryption.

Answer - B
This is mentioned in the AWS Documentation.
To mitigate this form of data exposure, AWS Managed Microsoft AD provides an option for you to enable LDAP over Secure Sockets Layer (SSL)/Transport Layer Security (TLS), also known as LDAPS. With LDAPS, you can improve security across the wire and meet compliance requirements by encrypting all communications between your LDAP-enabled applications and AWS Managed Microsoft AD directory.
Since the ideal and correct approach is specified in the AWS Documentation, all other options are incorrect.
For more information on using LDAP in AD, please visit the below URL
https://docs.aws.amazon.com/directoryservice/latest/admin-guide/ms_ad_ldap.html