Which situation best shows irony?

A.
A school nurse often misses work because she has an unhealthy lifestyle.

B.
A school nurse, who is usually busy, has a day with no student visits.

C.
A school nurse sends five sick students home one afternoon.

D.
A school nurse is married to one of the teachers.

The situation that best shows irony is A. A school nurse often misses work because she has an unhealthy lifestyle. This is ironic because a nurse, whose role is to promote and ensure good health, is unable to fulfill her duties due to her own unhealthy habits.