Answer:Explained below
Explanation:
Immune system is a response of body with respect to external factors like viruses,bacteria etc.It provides protection from external harmful agents .
Cancer cells are born due to genetic changes and When cancer cells able to evade the immune system they form tumors.cancer weaken the immune system by reaching the bone marrow and the bone marrow makes the blood cells which helps fighting the infection .Cancer can stop the making of such blood cells and weaken the immune system .
