The correct answer is option C that is, reducing the size of the tumor.
Debulking refers to the reduction of as much of the volume of a tumor as possible. It is generally attained by surgical removal. When done for a curative purpose, surgical debulking of tumors is called cytoreductive surgery or cytoreduction.
The process of debulking eradicates a portion of the tumor to make it smaller and more receptive to radiation therapy or chemotherapy.