The pronoun that replaces the underlined word correctly is <em>them </em>. The function of a pronoun is to be used instead of a noun or a noun phrase. In this case, in order to <em>avoid the repetition</em> of the words "The runners", the personal pronoun <em>them</em> is used and it is taking the role of an i<em>ndirect object </em> for the verb <em>offered </em>. "...Speedy Shoes offered <em>them</em> each a free pair of training shoes."
