Question

Because a flock of sheep needs protection ______ shepherd guard them.
please fill the blink from given below answer.
1) ,

2) '

3) ;

Answer 1

Thank you for asking the question!
Because a flock of sheep need protection, a shepherd guards them. 
In this sentence comma was missing as well as the article ''a'' . These minors grammatically errors can totally alter the meaning of a sentence making it grammatically inaccurate. Thus comma is used to add pause or after a fragment.
Hope it helps.