Final answer:
Tumor antigens are self-antigens that are inappropriately expressed on abnormal cells, such as cancer cells, and can elicit an immune response.
Step-by-step explanation:
Tumor antigens are self-antigens that are inappropriately expressed and found on abnormal cells. The correct answer to the student's question is a) Self-antigens. Tumor antigens can be targeted by the immune system because they differ from the normal complement of self-proteins that are typically present on healthy cells. These antigens can stimulate an adaptive immune response, which is part of the body's defense against cancer cells.
Tumor antigens are self-antigens that are inappropriately expressed and found on abnormal cells. Self-antigens are molecules that are normally present in the body but are recognized as nonself by the immune system when present on abnormal cells like cancer cells. These self-antigens trigger the immune system to react and eliminate the abnormal cells.