I certainly do not approved . . . . . . . . your riding your motorbike over the speed limit. A. on B. about C. in D. of

The correct answer is D. of.

The preposition “of” is used to indicate possession or association. In this case, the speaker is expressing disapproval of the person’s riding of the motorbike. The motorbike is associated with the person, so the preposition “of” is used.

The other options are incorrect because they do not convey the speaker’s disapproval in a natural way.

• The preposition “on” is used to indicate location or position. In this case, the speaker is not expressing disapproval of the location of the motorbike.
• The preposition “about” is used to indicate a topic or subject. In this case, the speaker is not expressing disapproval of a topic or subject.
• The preposition “in” is used to indicate a location or position inside something. In this case, the speaker is not expressing disapproval of a location or position inside something.