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