What is the basic unit of matter?

Atoms constitute the fundamental units of matter, and are a constituent of each element. In large part, the mass of an atom is determined by its positively charged  protons and neutral neutrons.

Explanation:

ya welcome BC

Brainliest pl?

In turn, the atom is the fundamental unit of matter…, that is, of an element. The number of positively charged protons and neutral neutrons in an atomic nucleus account for most of the mass of an atom

Explanation:

the core of the sun is so hot and there is so much pressure, nuclear fusion takes place, hydrogen is changed to helium. nuclear fusion creates heat and photons. when the heat reaches the earth it warms the molecules of the atmosphere, and they warm other molecules and so on.

the answer is a or when it says crossing over