Final answer:
Atoms cannot be created or destroyed in chemical reactions; they are just rearranged to form new compounds. The true statement is that atoms are conserved during chemical processes.
Step-by-step explanation:
The correct statement about atoms is that an atom cannot be created or destroyed by chemical reactions. In fact, atoms are merely rearranged during reactions to form new substances. This principle is known as the law of conservation of mass.
Atoms of different elements can indeed combine during chemical reactions in simple whole number ratios to create chemical compounds. Therefore, the true statement about atoms is A) An atom cannot be created or destroyed by chemical reactions.