Which sequence represents a deletion of this section of DNA?

A—C—T—C—G—A—T

A—C—T—A—T

A—C—T—C—C—T—T

A—T—C—T—G—G—A—T

A-C-T-A-T represents the deletion, both C and G are deleted from the sequence

Explanation:

the father in the first generation probably had the recessive colorblind trait in his x chromosome. if he and his wife both had the colorblind trait, even if she had 1 recessive and 1 dominant, then that trait would be passed on to their kids.

(since you didn't attach the family tree this is just an assumption)