The proportional graph that corresponds to M = 3n is: Graph C.
<h3>What is a Proportional Graph?</h3>
The constant of proportionality, k, of a proportional graph is given as, y/x. The graph is expressed by the equation, y = kx.
The equation given, M = 3n, represents a proportional relationship where k = 3.
Using a point on graph C, (400, 1,200):
k = 1,200/400
k = 3
Therefore, the graph that corresponds to the situation is: C.
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