1. A question answering system comprising: a question input unit that is input (to?) a question; a search unit that executes search processing on a basis of the input question; an answer candidate extraction unit that extracts an initial answer candidate on a basis of a result of the search processing executed by the search unit; an answer candidate inspection unit that inspects the initial answer candidate extracted by the answer candidate extraction unit; and an answer output unit that outputs a secondary answer candidate selected by the answer candidate inspection unit, wherein: final the answer candidate inspection unit executes search processing with using a query including the initial answer candidate extracted by the answer candidate extraction unit, the answer candidate inspection unit determines whether or not each word of a sentence, which is obtained as a result of the search processing executed by the answer candidate inspection unit, has a similar lexical meaning to a lexical meaning of each word of the input question, and the answer candidate inspection unit selects an initial answer candidate contained in a query, which is determined to have the similar lexical meaning, as the secondary answer candidate.