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

. two boys in blue karate suits and red belts

Choose your answer from: (a). are doing style to one another in a homemade karate mincing thing. (b). are standing on a stage in a school cafeteria and they are doing a karate routine in unison. (c). start to split into two groups to cover the left side of the mat. (d). and black shirts are working by lifting up hualists and throwing them to the sides of a mat or a mat a place.
The answer is:
(b).