I am working on first lab, but not seeing an option for enabling Multi-AZ

I am working on the first lab –Deploy an Amazon RDS Multi-AZ and Read Replica in AWS, but not seeing an option for enabling Multi-AZ. I went to database and modify but don’t have an option like it does in the video:

Multi AZ deployment:

–specifies if the DB instance should have a standby deployed in another availability zone.

Yes 

No

Please advice.