Answer:
The answer is D.
Explanation:
The given situation in the question where an Adenine nucleotide is swapped for a Thymine nucleotide, which as stated are complimentary of each other just like guanine and cytosine, can cause all three types of mutations, frameshift nonsense, frameshift missense and silent because the situation is not specific to either of them. There is no information whether the change resulted in a change in the amino acid structures or not. In this case the best answer is D.
I hope this answer helps.
The data given regarding the alleles are as follows
black(B)-dominant , chocolate(b) - recessive
normal vision - dominant, progressive retinal atrophy - recessive
normal hip joint - dominant, hip dysplasia - recessive
lets first consider one trait
parents are heterozygous
when crossed Bb x Bb
offspring BB Bb Bb bb
--------black----- chocolate
the probability of dogs being black - 3/4
dogs being chocolate - 1/4
likewise for the other two traits
probability of normal vision - 3/4 and retinal atrophy - 1/4
probability of normal hip joint - 3/4 and hip dysplasia - 1/4
we have to calculate the probability of 1st pup being born is
chocolate - 1/4
normal vision - 3/4
normal hip - 3/4
since all these traits should be acquired the probability of having the above three traits is calculated by getting the product of individual probabilities
therefore answer is 1/4 x 3/4 x 3/4
probability = 9/64