What is the antecedent of the pronoun in the parentheses?

Anyone who wants to attend next Saturday’s dance at the Rotary Club can pick up (his or her, their) ticket at the information booth on Vincy Street.]]> Is the antecedent singular or plural?

Anyone who wants to attend next Saturday’s dance at the Rotary Club can pick up (his or her, their) ticket at the information booth on Vincy Street.]]> Anyone who wants to attend next Saturday's dance at the Rotary Club can pick up his or her ticket at the information booth on Vincy Street. Type the correct pronoun into the box, then submit it and say the sentence.

Anyone who wants to attend next Saturday’s dance at the Rotary Club can pick up (his or her, their) ticket at the information booth on Vincy Street.]]>