<span>A. Even the best soldiers can make minor mistakes that put others at risk.
maybe? not sure really</span>
A.its should be the correct answer because it’s is the short form of it is.
The correct answer is B) because a run-on sentence is a sentence which is incorrectly punctuated. In this case, B doesn't have the right punctuation mark. Instead of a comma (,) perhaps a semicolon (;) should be used.