Which type of genes, when abnormally activated, can result in cancer?

A) tumor suppressor genes
B) apoptosis initiator genes
C) proto-oncogenes
D) DNA repair protein genes
E) apoptosis executioner genes

Proto-oncogenes are normal genes that can become oncogenes when they are mutated or abnormally activated. Oncogenes promote cell growth and division, and when their activity is uncontrollably increased, they can lead to the development of cancer. Tumor suppressor genes, on the other hand, normally prevent cancer development by regulating cell growth and division, and mutations that inactivate tumor suppressor genes can also lead to cancer. However, the question specifically asks about genes that are abnormally activated, which is characteristic of proto-oncogenes. Apoptosis initiator and executioner genes regulate programmed cell death, which plays a role in cancer, but their abnormal activation is not directly linked to cancer development. DNA repair protein genes are involved in maintaining the integrity of the genome, and mutations in these genes can increase the risk of developing cancer, but their abnormal activation is not usually associated with cancer.