Asummary demonstrates which of the following?

a. the summary author clearly understands the concept covered in the original work.

b. the summary author is able to reword phrases and content from the original work.

c. the summary author can quickly scan a work and gather the main ideas.

i personally think it's a but i'm not sure.

You are correct - it's A the author can clearly understand the concept covered in the original work.

Typically the summary author can demonstrate their understand by rewording the original content and gather the main idea - but the point of summarizing is to show a clear understanding.

explanation:

it refers to the definition of full-contact sports, where the condition is that the sport must have athletes must "purposely collide with each other