After his graduation, he had to pass through a period of privation.

Answer: Option A

Hardship : severe suffering or privation.
Uncertainty : the state of being uncertain.
Prosperity : the state of being prosperous.
Privacy : a state in which one is not observed or disturbed by other people.
Privation : a state in which food and other essentials for well-being are lacking.

Synonym of Privation is Hardship