Which of the Following Statements Is NOT Correct

Which of the following statements is NOT correct?

A) Exchange-traded funds (ETFs) are designed to mimic particular stock indexes and are traded on a stock exchange.
B) ETFs have very high expense ratios.
C) ETFs differ from most open-end and closed-end funds in that they are not actively managed.
D) One disadvantage of ETFs is that each purchase of additional shares must be done through the exchange where they are traded.