Why are immunosuppressants called “a necessary evil”?

Immunosuppressants are drugs or medicines that lower the body's ability to reject a transplanted organ.

Explanation:

These can cause and increased risk of infection and malignancy. Many of these drugs also impact adversely on patients' cardiovascular risk

answer; /// i believe that the correct answer is (c); ///when the lungs expand, they fill with air from the atmosphere;

answer; i believe the answer is moderate level;