A mother weighs her baby by holding the baby and stepping on a scale. Their combined weight is 143 pounds, and the mother's weight is 128 pounds. How much does the baby weigh? Let \( w \) be the baby's weight. Which equation can be used to find the baby's weight?
A. \( 143 - w = 128 \)
B. \( 143 - 128 = w \)
C. \( w + 128 = 143 \)
D. All of the above