Answer:
   (d) No. Slope is not constant.
Step-by-step explanation:
You want to know if the given graph shows a linear function.
<h3>Linear function</h3>
The graph of a linear function is a straight line. The points on the graph shown do not form a straight line, so the function is nonlinear.
<h3>Rate of change</h3>
The rate of change of a function is the ratio of "rise" to "run" between two points in the graph. This ratio is also called the "slope." For a straight line, the rate of change (slope) is constant. That is, a linear function has a constant rate of change. 
If the function is nonlinear, its rate of change is not constant. The converse is also true: if the slope is not constant, the function is nonlinear.
 
        
             
        
        
        
(4xy - 3z)²
(4xy - 3z)(4xy - 3z)
4xy(4xy - 3z) - 3z(4xy - 3z)
16x²y² - 12xyz -12xyz + 9z²
16x²y² - 24xyz + 9z², a perfect square trinomial.