Select the option that can be used as a one-word substitute for the given group of words.
A person who does not believe that God or Gods exist.

Correct option is B

The correct one-word substitute for "A person who does not believe that God or Gods exist" is (b) Atheist.
An atheist is someone who lacks belief in the existence of God or gods, which precisely fits the description given.

Example: "Despite growing up in a religious household, she identified as an atheist because she found no personal evidence to believe in a higher power."
Meanings of the other options:
• Irreverent: Showing a lack of respect for people or things that are generally taken seriously.
• Profane: Relating to or treating something sacred or serious with disrespect.
• Blasphemous: Showing disrespect or lack of reverence for God or something sacred.