Finish the following sentence with the best choice: To reinforce a paper project,

Choices:
- cut a piece of cardboard in equal size to the paper you want to strengthen, and glue the cardboard to the back of the paper design.
- cut a piece of cardboard in equal size to the paper you want to strengthen, and glue the cardboard to the front of the paper design.

Answer:
cut a piece of cardboard in equal size to the paper you want to strengthen, and glue the cardboard to the back of the paper design.