Which of the following statements is correct about the utility model patent application?

Which of the following statements is correct about the utility model patent application?

A. the summary of the instruction can be used as the basis for modifying the instruction.

B the attached drawings of the instruction manual should not only show the effect and performance of the product.

C. The text of the instruction manual can have tables and illustrations, such as flow charts, if necessary.

D if the drawings in the original specification are unclear, clear drawings can be added by redetermining the application date.

Correct answer: b