The second answer. Because “sus” is the only one which has the “s” because it is plural. If it would be “nuestro” it should had an “s” like “nuestros hijos son altos” or “tus hijos son altos”
1. Me pongo mis zapatos
2. Me pongo la crema de afeitar
3. Me pongo una camiseta, mis calzones, mis calcetines, mi pantalon y mis zapatos
