In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.
Q: The National Guard is a joint activity of the United States Department of Defense ( DoD ) composed of reserve components of the United States Army and the United States Air Force : the Army National Guard and the Air National Guard , respectively .
A:
The United States National Guard is an organization of the United States Army and the United States Air Force .