In superheroes, the ability to Fly (F) is dominant over not being able to fly (f). Superman can fly (Ff) (he has one dominant and one recessive trait). He marries Storm (from the X-men) who also has one dominant and one recessive trait (Ff), and can fly.

Explanation:

The question is incomplete.

We can build a Punnett square to find the offspring and then determine the probability that the descendents inherit the ability to fly.

Write the columns and rows titles:

           F    f  ← Superman's genes

   F

   f

   ↑

Storm's genes

Fill in the cells with the possible combinations:

           F    f

F         FF   Ff

f          Ff    ff

Homozygous FF:   1      can fly

Heterozygous Ff:  2      can fly

Homozygous ff:     1       cannot fly

                 Total:    4

Homozygous FF:   1/4      can fly

Heterozygous Ff:  2/4      can fly

Homozygous ff:     1/4       cannot fly

Since the ability to fly (F) is dominant, the heterozygous Ff descendents are able to fly. That is 3/4.

Only the homozygous ff are not able to fly. That is 1/4.