If XN is the dominant allele for normal vision and Xn the recessive allele for colour-blindness, a boy with the genotype YXn will
A.
Have normal vision
B.
Be colour-blind
C.
Be totally blind
D.
Be a carrier of colour-blindness
Answer: D
To see detailed solution to this question and thousands of other questions offline, download TestDriller UTME. Practice rigorously for UTME, enjoy educational games, summary of JAMB literature books, compete with your peers, win prizes and more.