Mutant Forms of Tumor-Suppressor Genes Act _____; Both Copies of the Gene

Mutant forms of tumor-suppressor genes act _____; both copies of the gene must be _______ before their protective function is lost.

A) as dominant genetic traits,mutated or deleted
B) as dominant genetic traits,preserved
C) recessively,mutated or deleted
D) recessively,preserved
E) like sex-linked recessive genes,mutated or deleted