Read the selection from the third paragraph of the article.

The helmet incorporates engineering principles more commonly seen in building cars. The outer shell is softer and more bendable, made from flexible plastic. Beneath it is a layer of more than 500 small columns, each measuring an inch or so long, which absorb force and also twist and move sideways.

Which phrase from the paragraph BEST helps you understand HOW the new helmet helps make football safer for players?

A. engineering principles
B. flexible plastic
C. absorb force
D. move sideways