Question: Full pod shape (F) is dominant to constricted pod shape (f), and yellow pod color (Y) is dominant…

Full pod shape (F) is dominant to constricted pod shape (f), and
yellow pod color (Y) is dominant to green pod color (y) in pea
plants. A pure-breeding green plant with full pods is crossed with
a pure-breeding yellow plant with constricted pods. The offspring
are then testcrossed. How many different phenotypes do you expect
in the offspring?

a. one

b. two

c. three

d. four

e. cannot be determined

please explain