東大形式文法上の不要な単語を一単語抜く問題(1)(2)

1. Girls are so far ahead of in the academic battle of the sexes that boys have
become an educational underclass.
2. An international trading city, headquarters of the overseas Portuguese empire, Lisbon was filled at once with local merchants, workers who bound for the Indies or Brazil, the widows of sailors lost at sea, and impoverished farmers or their children who had fled the arid countryside.

自分の答え
(1)of (2)who
正しい答えと理由が知りたいです。