In which one of the following situations should revenue be recognized? a. The earnings process has begun

Question:

In which one of the following situations should revenue be recognized?
a. The earnings process has begun and cash collectibility is reasonably ensured.
b. The earnings process has begun and cash has been collected.
c. The earnings process is substantially complete and cash collectibility is not yet reasonably ensured.
d. The earnings process will soon begin and cash has been collected.
e. The earnings process is substantially complete and cash collectibility is reasonably ensured.