Question

O

A. a male with at least one dominant allele.
O
B. a male with two dominant alleles.
O
c. a female with two dominant alleles.
O
D. a female with at least one dominant allele.
SUBMIT

Answer 1

D

Step-by-step explanation:

The squares represent 'male individuals', while circles represent 'females.' Therefore, child 'A' must be a female.

Attached earlobes can only be seen in individuals who have two recessive alleles. The color 'white' represents an individual who has at least one dominant allele, whereas the shaded color is referred to as an individual with two recessive alleles.

As child 'A' has a sister who has the recessive trait of attached earlobes, either of their parents has a recessive allele.

Child 'A' is not a shaded individual (i.e. she does not have attached earlobes). This means that she has at least one dominant allele. In other words, she may have one or two dominant alleles. In case of two dominant alleles, child 'A' may receive two dominant alleles, one from the father and the other from the mother. Another possibility is that she may receive one dominant allele from either parent and one recessive allele from the other parent.

Therefore, the answer to this question is D.