The correct answer is C. competition.
A contest is a competitive activity held between two or more people or groups. A comparison is a statement of the similarities and differences between two or more things. Cooperation is the act of working together to the same end.
In the context of the question, the word “keen” suggests that the competition is intense. This is supported by the fact that the word “keen” is often used to describe competition in sports, business, and other areas.
The other options are not as relevant to the context of the question. A contest is not necessarily intense, and a comparison does not involve working towards the same end. Cooperation is possible in a competitive environment, but it is not the focus of the question.