Answer:
Correct answer is C. an economic downturn
Step-by-step explanation:
C is correct answer because it led to his downfall. Economical problems became a large issue for the government, and that is why he lost presidential election in 1993.
A is not correct of course, because collapse of Soviet Union was seen as a success of foreign policy.
B is not correct because The Gulf War didn't affected USA that much and the campaign was successful.
D is not correct because this was more attributed to his successor, Bill Clinton.