Answer:
The correct answer is B. Radioes
Step-by-step explanation:
The plural of radio is radios or radio, in a more general context.
The example here mentions radio, as a noun and not as a verb, as in the rule in the present simple with the verbs in third persons, which end in “o” you add an –es suffix, for instance: She goes to the gym every day. Nevertheless, with nouns, this rule doesn’t apply. So, that is why it’s Radios, and not Radioes.