A child is born at 8.5 lbs and gains the weight of 1.5 lbs every month. What is the function that will tell me how much the child weighs at any given month?

To determine the function that describes the child's weight as a function of time in months, we can start with the initial weight and account for the monthly weight gain.

• The child is born at a weight of 8.5 lbs.
• The child gains 1.5 lbs every month.

Let \( x \) represent the number of months since birth. The child's weight will be the initial weight plus the weight gained over time. Therefore, the function can be expressed as:

\[ \text{weight} = \text{initial weight} + \text{(weight gain per month)} \times x \]

Substituting the known values:

\[ \text{weight} = 8.5 + 1.5x \]

This matches the form of function \( c \):

c. weight = 1.5x + 8.5

So, the correct answer is c.