Which of the following behaviors is typical for a 5-month-old infant during a well-baby checkup?

At 5 months of age, an infant typically demonstrates a range of developmental milestones. One of the key behaviors observed at this age is the ability to roll from a prone position (lying on the stomach) to a supine position (lying on the back). This rolling action is an important physical milestone that indicates the developing strength and coordination of the infant's muscles.

This behavior signifies that the infant is starting to gain more control over their movements, as it requires the coordination of various muscle groups. The ability to roll over is a precursor to further developmental skills, such as sitting up and crawling, which generally occur later.

While other behaviors listed, such as transferring objects from hand to hand, are also part of infant development, they typically occur a bit later, around 6 to 7 months. Similarly, showing signs of stranger anxiety usually develops closer to 6 to 8 months, as infants start to recognize familiar faces and may react differently to unfamiliar people. Sitting without support is generally expected around 6 months to 8 months. Therefore, rolling from prone to supine is the most characteristic behavior for a 5-month-old during a well-baby checkup.