Correct option is D
The correct answer is (d).
This statement describes a classic dominant negative mutation, where the mutated protein interacts with the wild-type protein and disrupts its normal function. This is a key characteristic of dominant negative mutations.
Incorrect options-
Option (a) describes a gain-of-function mutation leading to constitutive activity, not necessarily dominant negative.
Option (b) shows a mutation with reduced enzyme activity but with no dominant negative effect because heterozygotes maintain normal function (haplosufficiency).
Option (c) describes a recessive mutation affecting transcription factor binding only when both alleles are mutated, indicating loss-of-function but not dominant negative.
