Complete the sentence with the present simple or past simple form of the verb in brackets. Tennis ... on a clay, grass or hard court. (PLAY)

The sentence "Tennis ... on a clay, grass or hard court. (PLAY)" requires us to use the correct form of the verb "play" in either present simple or past simple tense.

Since the sentence describes a general fact about tennis, we should use the present simple tense. Tennis is a sport that is generally played on these surfaces.

Therefore, the correct form of the verb is "is played".