Answer:
C) Increases in operating expenses may indicate inefficiencies, and decreases in operating expenses may be detrimental to long-term sales growth.
Step-by-step explanation:
You should always be very careful and meticulous when you are analyzing operating expenses and all expenses in general. Businesses should always try to lower their expenses, since profit is determined by revenue - expenses.
But when you are evaluating operating you cannot do it as a separate factor. For example, sales commissions are operating expenses, but when they lower you are in trouble. But other operating expenses are not that beneficial for a company, for example rent, utilities, etc.