Coracias garruius is a blue bird with an orange-brown back. the offspring of this bird have an effective defense mechanism. The young birds vomit and cover themselves in a foul-smelling orange liquid when they sense a threat by predators. Which two systems alert the young bird to the danger and help produce the vomit it uses as a defense?

A- nervous and digestive systems
B-integumentary and muscular systems
C-immune and respiratory systems
D- excretory and reproductive system