The given answer "あそぶ" is the correct answer because it is the dictionary form of the verb "あそびます". In Japanese, verbs have different forms depending on the tense, politeness level, and sentence structure. "あそぶ" is the plain form of the verb, which is used in casual conversations and non-polite situations. "あそびます" is the polite form, used in formal situations or when speaking to someone of higher status. Therefore, "あそぶ" is the correct answer as it matches the given verb in its dictionary form.