Two identical twin boys had different fingerprints. This proves that

A.

the fingerprint is a sex-linked character

B.

the genotypes of the twins are similar

C.

the phenotypes of the twins are similar

D.

there are morphological variations

E.

there are physiological variations in the twins

Correct answer is D

Morphological variation includes aspects of the outward appearance i.e shape, structure, color, pattern, and size.