The correct answer is 'c'
Irascible, irascible means to be easily angered.
The answer which is an example of a theme with a dual nature is D. people who work hard learn values but may not prosper.
The other sentences are pretty linear and expected - a person works hard and is successful in life. D is somewhat different, which is why it has two natures, or a dual nature.
Answer:
The Monitor Evaluator (thought-oriented)
The Specialist (thought-oriented)
The Plant (thought-oriented)
The Shaper (action-oriented)
The Implementer (action-oriented)
The Completer/Finisher (action-oriented)
The Coordinator (people-oriented)
The Team Worker (people-oriented)