A- Graph B shows exponential growth of a population.
Graph B is a type of exponential equation where y=a(b)^x
"a" is the initial value that intercepts the y-axis in the above equation.
"b" is the value that every value thereafter is growing (multiplying by). Note, if "b" is 1- your value is not growing (since it is staying at it's original 100%). If "b" is, for example 1.5 your value is growing by 50% each time (1 gives you your original 100%, and the .5 gives you an additional 50% on top of that).
"x" is your input, and here it is the exponent because you are multiplying "b" to the power of your input for each value.