A: Which option to choose
I do have this 9.10 ACR and I have double checked from within Ps.
Has been answered many times if do a search in the forum .
This is a confirmed bug and it's a false message. You can safely check to Don't show again and hit Open Anyway.
It will be fixed in the next release, probably.
Cant see. Are you from Adobe or a customer like me?
Customer like you ... as (nearly) all participants of this Forum - It's a user-to-user forum operated by Adobe where some Adobe staff checks in from time to time too (Staff badge).