The correct answer to this open question is the following.
Although there are no options we can say the following.
Dr. Carmine is lecturing parents about crying and the well-being of young infants. The statement she should make is: "use a baby sling if possible, as kangaroo care helps babies cry less."
Mothers want the best for their babies. And that is why Dr. Carmine recommends the use of baby slings for the babies to cry less. It is a safe place for babies. The baby still has direct contact with the mother, strengthening the relationship. And if the mother uses to take a walk, with the baby in the sling she adds some weight to the exercise.