Final answer:
The correct answer is O.D. Sabes.
Step-by-step explanation:
The correct answer is O.D. Sabes because the question is asking 'Do you know how to play tennis?'. In Spanish, we use the verb 'saber' when talking about knowing how to do something. The pronoun 'tú' corresponds to the second-person singular, which is 'sabes' in the present tense of the verb 'saber'.
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