The degrees were awarded in the annual . . . . . . . .

The correct answer is D. convocation.

A convocation is a formal ceremony at which degrees are conferred by a university or other educational institution. It is typically held once a year, and may include speeches, music, and the presentation of awards.

A conference is a meeting of people for a particular purpose, such as to discuss a topic or to share information. A convention is a meeting of people who belong to the same organization or group. A convolution is a mathematical operation that is used to combine two functions.

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