If a Storm Can Survive the West Side of an Easterly

Multiple Choice

If a storm can survive the west side of an easterly wave,there is a chance it can intensify into a hurricane.Which of the following is correct regarding an easterly wave?

A) The west side of the wave has rising,stable air.
B) The west side of the wave has descending,unstable air.
C) The east side of the wave has rising,unstable air.
D) The east side of the wave has descending,stable air.