Which two actions can an administrator use to automate this process?

The VP of Sales wants to enforce a new B2B sales process for the sales representatives. For example, if an opportunity is still in the Prospecting stage one day after the next stage is due, the Deal Status should change to Stalled and the number of deals stalled on the account should be incremented.

Which two actions can an administrator use to automate this process? Choose two
A . Cross-object workflow field update
B . Workflow Field update on the opportunity
C . Workflow field update on the account
D . Roll-up summary field on the account

Answer: B,D