The most difficult kind of frustration a person must deal with is probably

a. general frustration when everything seems to be going wrong

b. getting poor grade after working hard on school project

c. not being appreciated on the job

d. financial frustration

D. Financial frustration Most people can deal with general frustration, getting poor grades, and not being appreciated on the job but if you do not have enough money that causes major problems in life not just a general things are going wrong feeling. Financial frustration is the #1 cause for divorce in the USA.

The best answer is a) a general frustration: if everything is going wrong then you can't even find solace in other aspects of life, unlike in D. when if the family life is going well, then the person might at least find some relief there.