What Is One Reason Why Tumor-Suppressor Genes Make Poor Druggable

What is one reason why tumor-suppressor genes make poor druggable targets?

A) Cancer-causing mutations in tumor-suppressor genes result in loss of function.
B) Mutant alleles of tumor-suppressor genes generally result in a greater activity of the protein, which makes inhibiting the proteins more difficult.
C) Most drugs cannot distinguish the normal and mutant forms of the tumor suppressor proteins.
D) Drugs that can target-tumor suppressor proteins are difficult to deliver to cancer cells.