This is a test of commonsense with single/multi-choices. Complete the next sentence:

A screen appears with instructions how to attach an instep bike trailer. a man

Available options: A. is seen riding dirt bikes in a lane. B. replaces the main tire using a spare tire along with another. C. is showing how to attach an instep bike trailer on the back wheel of a bike. D. does a routine on a tire.
The answer is:
C.