The right anser is "B) All of the contestants have their story to tell."
Explanation: The pronoun and the antecedent must be in agreement. In this case, in the sentence: "All of the contestants have their story to tell". The pronoun is "their" so the antecedent, has to be a name in the plural, so that there is conconcordancia in the phrase. The antecedent is "Contestants" which is a plural noun. Thus "contestants" and "their" are in agreement.
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