Answer:


Step-by-step explanation:
we know that
A relationship between two variables, x, and y, represent a proportional variation if it can be expressed in the form
or 
In a proportional relationship the constant of proportionality k is equal to the slope of the line m, and the line passes trough the origin
so
case A)
Is a linear equation but does not passes trough the origin
case B) 
Is a linear equation and passes trough the origin-----> represent a proportional relationship
case C)
Is a linear equation and passes trough the origin-----> represent a proportional relationship
case D) 
Is a linear equation but does not passes trough the origin