The atoms in a chemical reaction are responsible for the ...

a) Mass

b) Energy

c) Temperature

d) explosion

I'm pretty sure it's C but I'm not 100%

The mass is also due to atoms and the temperature rise is also due to atoms collision!

but the most appropriate answer is A!

Chemical reactions occur when different atoms and molecules combine together and split apart. For example, if Carbon (C) is burnt in Oxygen (O2) to form Carbon Dioxide, a Chemical Reaction occurs.

So, during chemical reactions, new product atoms are not created, and old reactant atoms are not destroyed. Atoms are rearranged as bonds are broken and formed. In all chemical reactions, mass is always conserved.