Which of the Following Statements About Gross Profit Percentages Is

Which of the following statements about gross profit percentages is correct?

A) Because gross profit percentages are so consistent from period to period,they are not very useful for analyzing one company over time.
B) Because gross profit percentages are so variable across industries,they are most useful in comparing companies from different industries.
C) Because gross profit percentages are so variable across industries,they are more useful in analyzing one company over time.
D) Because gross profit percentages are so consistent across industries,they are most useful in comparing companies from different industries.