I believe the pronoun in this sentence is <u>your key</u>.
The correct answer for the given question above would be option A. Based on the given sentence above, the phrase that is in bold "Working crossword puzzles", is an example of a participial phrase. Participial phrase is a phrase consisting of a present or past participle, and<span> any </span>modifiers<span>, </span>objects<span>, and </span>complements<span>. Hope this helps.</span>
