What could be the cause of this?

The administrator of universal containers is testing an approval process in a refreshed developer pro sandbox and is finding that none of the notification emails are being sent to the approvers.

What could be the cause of this? choose 2
A . The Deliverability Access Level setting is incorrect.
B . Workflow emails only work in full sandboxes.
C . HTML templates are not available in sandboxes.
D . The email addresses for the users are incorrect

Answer: B,C