Which of the following would be most likely to lead to cancer?
a. amplification of a proto-oncogene and inactivation of a tumor-suppressor gene.
b. hyperactivity of a proto-oncogene and activation of a tumor-suppressor gene.
c. failure of a proto-oncogene to produce a protein and amplification of a tumor-suppressor gene.
d. hyperactivity of both a proto-oncogene and a tumor-suppressor gene.
e. failure of both a proto-oncogene and a tumor-suppressor gene to produce proteins.

Option A

Explanation:

Cancer can be defined as the undefined growth of cells in the body which leads to tumor formation. The term amplification of the the proto-oncogenes refers to the increases in the copy number of the genes.

This is caused due to the irregulation in the cell cycle and due to this cancer occurs in the body.

The tumor suppressing gene gets deactivated during this time as it can suppress the activation of proto-oncogens which leads to cancer.

hence, the correct answer is option A.