Assertion: Different species of microbes seem to have evolved to home in on different parts of the body.
Reason: In part, this selection is connected to their point of entry. If they enter from the air via the nose, they are likely to go to the lungs.
a) If both assertion and reason are true and reason is correct explanation of assertion.

b) If both assertion and reason are true and reason is not the correct explanation of
assertion.
c) If the assertion is true but reason is false.
d) If both assertion and reason is false

Dear Student,
a) Both assertion and reason are true and reason is correct explanation of assertion.
Different species of microbes seem to have evolved to home in on different parts of the body from where this selection is connected to their point of entry. If they enter from the air via the nose, they are likely to go to the lungs, and can cause tuberculosis. If these microbes enter through mouth, they can stay in the intestine lining. So, we can say that different microbes enter in human body in different ways and cause damage or infect different organs.
Regards