The average weight, in ounces, of a baby for the first six months of life can be estimated using the equation y = 6x + 120, where x represents the number of weeks. What is the meaning of the slope of this equation?

A.
A baby gains an average of 120 ounces per week.

B.
A baby weighs about 6 ounces when it is first born.

C.
A baby gains an average of 6 ounces per week.

D.
A baby weighs about 120 ounces when it is first born.