A coefficient is a numerical or constant quantity placed before and multiplying the variable in an algebraic expression (e.g. 4 in 4x).
The 2 and + are out since they don't have variables(and the + is just a +).
So 4 and x are left. x is a variable, not a coefficient, so the last(and correct) answer is 4.
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hope it helps
<span>its C. Alan has 13 CDs, Tom has 16 CDs, Barbara has 23 CDs !</span>
