The correct answer of the given question above would be the first option. A noun clause is a dependent clause that functions as a noun and is usually introduced by the words that, how, whatever, what, when, where, whether, which, whichever, who, whoever, whom, whomever and why. The sentence from the paragraph that contains a noun clause is this: <span>I know without a doubt that I should drink more water after exercising. </span>
