An Elderly Man Saw a Flyer About a Free Influenza

An elderly man saw a flyer about a free influenza immunization clinic at the senior citizens' center.Which of the following would be his best choice of action?

A) Attending the free immunization clinic to say hello to his social contacts
B) Bringing his elderly wife and both receive the influenza immunization
C) Realizing that at his advanced age,he's already immune to influenza,and so he does not need to attend the clinic
D) Recalling that he and his spouse received an influenza vaccine last year,and so they already have immunity