Help me pls someone???

gas vibrate and move freely at high speeds so the answer would be

(drumroll please) D very energetic

-haha hope this is correct and if not i hope it at least help but either way have a good rest of your day :)

Explanation:

because u need two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei to form isotopes.

so since they all have the same shape? i mean maybe because m& m and reeses are both chocolates