What did you make . . . . . . . . the lecture? A. of B. in C. about D. on

The correct answer is: C. about

The word “about” is used to indicate the subject matter of something. In this case, the speaker is asking what the listener made the lecture about.

The other options are incorrect because they do not make sense in the context of the question.

• The word “of” is used to indicate possession or origin. For example, “I made a cake of chocolate.”
• The word “in” is used to indicate location or position. For example, “I made a cake in the oven.”
• The word “on” is used to indicate a surface or location. For example, “I made a cake on a plate.”

I hope this helps! Let me know if you have any other questions.