a fruit is most commonly _______?

A. modified root
B. a mature female gametophyte
c. mature ovary
d. a thickened style
e. enlarged ovule

Modified root

A thickened style

A mature ovary

a mature female gametophyte

a thickened style

To determine the correct answer, we need to understand the botanical definition of a fruit. A fruit is the mature ovary of a flowering plant, typically containing seeds. With this knowledge, we can evaluate the options:

A. Modified root: This is not the correct answer since a fruit is not a modified root.

B. Mature female gametophyte: This is incorrect because a fruit is not a gametophyte (the female gametophyte is the embryo sac, which is not the same as a fruit).

C. Mature ovary: This is the correct answer. A fruit is most commonly a mature ovary of a flower.

D. Thickened style: This is not the correct answer. The style is a part of the female reproductive structure of a flower, but it does not describe a fruit.

E. Enlarged ovule: This is not the correct answer. While the ovule becomes a seed within the fruit, the entire fruit is not an enlarged ovule.

Therefore, the correct answer is C. A fruit is most commonly a mature ovary.