Why are two balls connected by a spring a good model for two atoms connected by a chemical bond?

A) The magnitude of the force one atom exerts on another is proportional to the stretch or compression of the bond between them.

B) If the two atoms get farther apart than the equilibrium interatomic distance, they attract each other.

C) Each spring represents a real microscopic coiled metal wire that connects two adjacent atoms.

D) If the two atoms get closer together than the equilibrium interatomic distance, they repel each other.

Note: I already tried A B C and A B and A D and none of these combinations are correct.

Researchers conducted an experiment to identify the effects of three different hand sanitizers on the growth of bacteria. the researchers grew one type of bacteria in twenty-four identical covered petri dishes. then, they opened eighteen petri dishes and applied the three hand sanitizers to six petri dishes each. they left the remaining six petri dishes closed as a control group. when the researchers measured the growth of bacteria two days later, the six dishes that had no hand sanitizer showed the least amount of bacterial growth. the researchers concluded that not using any hand sanitizer would lead to the least bacterial growth. which statement best explains why the researchers’ conclusion was not justified? the experiment tested too many variables. the control group was not treated the same as the experimental group. the sample size of twenty-four petri dishes is not large enough. the single type of bacteria is not adequate to make any conclusions.