Answer: C) We might go camping next weekend.
Explanation: Helping verbs are verbs that help the main verb in a sentence by extending its meaning. They can also add detail to how time is conveyed in a sentence. They are placed before the main verb. From the given options, the sentence that contains a helping verb, is the corresponding to option C: We might go camping next weekend, the main verb is "go" and the helping verb is "might."