What allows a gas to fill a container?

A.
the size of the particles in a gas

B.
the shape of the particles in a gas

C.
the constant motion of the particles in a gas

D. the absence of intermolecular forces among the particles in a gas

so is it a b c

No, the correct answer is C. The constant motion of the particles in a gas allows the gas to fill a container. The size and shape of the particles (choices A and B) can have an effect on the behavior of the gas, but they do not directly determine its ability to fill a container. Option D is incorrect because gases do have intermolecular forces, but these forces are generally weaker compared to those in liquids or solids.