单选题 One disadvantage of using the price/sales (P/S) multiple for stock valuation is that:

A、 profit margins are not stable over time.
B、 profit margins are not consistent across firms within an industry.
C、 sales are relatively stable and might not change even though earnings and value might change significantly.

【正确答案】 C

【答案解析】The stability of sales (relative to earnings and book value) can be a disadvantage. For example, revenues may remain stable but earnings and book values can drop significantly due to a sharp increase in expenses.