Which is the best description of competitive product analysis?

Which is the best description of competitive product analysis?
A) A competitor's product is purchased, disassembled, and the components tested in order to generate ideas for improving the quality of products.
B) An independent testing service, such as Consumers' Union, is hired to test and rate a group of similar products.
C) A company looks at all the competitors' products and rates them on a scale of 1 to 10.
D) This is the result of a consumer survey by the marketing department.
E) An independent firm conducts consumer research in order to rate competing products.