Answer:
Option B. -1
Explanation:
we have
![14a-72r-c-34d](https://img.qammunity.org/2020/formulas/mathematics/high-school/6dm2z0596yga59va3x5cgffoei05508d34.png)
we know that
The coefficient of a term is equal to the number that multiply the term
so
In this problem
14 is the coefficient of the a-term
-72 is the coefficient of the r-term
-1 is the coefficient of the c-term
-34 is the coefficient of the d-term
therefore
-1 is the coefficient of the c-term