Your client invested in your friend's start$-$up company a year ago, which has since earned a return of $150\%.$ Your client now wants to exclusively invest in start$-$up companies because they believe that all start$-$up companies offer high returns. As a finance professional, you recognize this behavior as $\_\_\_\_\_\_\_\_\_\_\_\_\_\_.$

Overconfidence

Anchoring

Representativeness bias

Conservatism bias