In which sentence is the underlined phrase an adverb phrase

Some critics argue that hamlet is a problem play others argue that it is a tragedy explain the difference between a problem playing a tragedy identify the characteristics of hamlet's that are typical probably that those that are typical of tragedy then decide which you believe is it is and explain why your answer should be at least 250 words

When aquinas realized that he could not find all the answers, he turned to

Think about the noes story. which fits best on the blank line above?