How do Class A shares differ from Class B shares in an open-end investment company?

Class A shares and Class B shares in an open-end investment company differ primarily in their fee structures, which is clearly outlined in the correct choice. Class A shares typically incorporate a front-end sales charge, which means that investors pay a commission upfront when they purchase the shares. This fee is deducted from the initial investment, thereby reducing the amount of money that is immediately invested into the fund.

In contrast, Class B shares do not have this front-end sales charge. Instead, they usually have a contingent deferred sales charge, which is a fee that investors pay only if they sell their shares within a certain period of time after purchasing them. This makes Class B shares potentially more appealing for short-term investors who may not want to pay any charges upfront.

It is important to note that while Class A shares might be attractive for long-term investors due to their front-end charge being less burdensome over time, Class B shares may keep more of the investment working for an investor initially but can result in higher costs when sold prematurely due to the deferred sales charges.

In summary, the distinction in the sales charge structures—where Class A shares require an initial fee while Class B shares impose a fee later upon sale—illustrates the fundamental difference between these two classes of shares.