All living organisms have evolved from a single common ancestor. The existence of which molecule lends the greatest support to this statement?

i believe the answer is a or 1

a chair, a bed, and a toothbrush

explanation:

i was told this before by a teacher, so yeah

when you breathe in, or inhale, your diaphragm contracts (tightens) and moves downward. this increases the space in your chest cavity, into which your lungs expand. the intercostal muscles between your ribs also enlarge the chest cavity. they contract to pull your rib cage both upward and outward when you inhale.