What is the probability that a female offspring of the cross that is shown above would have a recessive allele for Duchenne muscular dystrophy disorder?

Option D

Explanation:

Given -

Duchenne muscular dystrophy is an X-linked recessive disorder.

The mother is heterozygous recessive for the Duchenne muscular dystrophy.

In this case if X' represent the affected allele, the genotype of affected female would be  XX'

Also, the father is unaffected but is the carrier of recessive affected allele. Hence, Genotype of father would be X'Y

Cross between XX' and X'Y would give the following offspring -

XX', XY, X'X', X'Y

All the female offspring will have recessive allele for Duchenne muscular dystrophy disorder

Hence, the probability of a female offspring with recessive allele for Duchenne muscular dystrophy disorder will be 100 percent

Hence, option D is correct

Read more on -

the answer to your question is b

i'm thinking (a) to keep sand in place; ////////////

explanation: a sand fence or sandbreak, like a snow fence, is used to force windblown, drifting sand to accumulate in a desired place. sand fences are employed to control erosion, sand dune stabilization, keep sand off roadways, and to recruit new material in desert areas.