In any chemical reaction, the quantities that are preserved are O A. the number of moles and the volumes B. the number of molecules and the volumes 0 C. mass and number of atoms D. mass and moles

Observation and experimentation have led many scientists to accept a theory about the origin of the universe. this theory is called the big bang theory. scientific evidence collected and observed by scientists around the world suggests that the universe is ever expanding from a hot and dense initial state. what makes this a scientific theory? (2 points)