Purple Flower (A)is Dominant Over White Flower (A),and Tall Stem

Multiple Choice

Purple flower (A) is dominant over white flower (a) ,and tall stem (B) is dominant over short stem (b) .The Punnett square represents a cross between two dihybrids (AaBb × AaBb) .
Examine the figure above,and answer the following question(s) .
-In the figure above,what is the ratio of phenotypes in this case?

A) 1: 1:1:1
B) 3:1
C) 6:3:3:1
D) 9:3:3:1
E) 15:1