Shivering occurs when many muscles contract a little bit all at once.
Shivering heats the body.
Many muscles contracting a little bit all at once heats the body.
what does muscles contracting a little bit all at once do?
Options:
[1] biceps
[2] cause death
[3] respiration
[4] staying warm
[5] rapid expansion
[6] movement
[7] heat the body
[8] to move people