What is the primary purpose of chemotherapy in cancer treatment?

Chemotherapy primarily aims to kill or inhibit the growth of cancer cells. This is achieved by using various drugs that target rapidly dividing cells, which is characteristic of cancerous tissues. The mechanism of action for chemotherapy agents typically involves disrupting the cancer cell cycle, leading to cell death or preventing further proliferation.

While there are other aspects to cancer care, such as improving a patient's overall well-being or boosting the immune system, these are not the primary intent of chemotherapy. Surgical removal of tumors can be a part of treatment, but it does not fall under the umbrella of chemotherapy, which is a systemic treatment rather than a localized surgical approach. Therefore, the focus of chemotherapy is distinctly on its role in directly combating cancer cells, rendering the option that states its purpose as targeting cancer cells the correct choice.