Conduction occurs more easily between solids and liquids. this is because the particles in gases are a) farther apart and move faster. b) closer together and move faster. c) further apart and move more slowly. d) closer together and move more slowly.

The correct answer is
D) closer together and move more slowly.

In fact, in solids and liquids the particles are closer to each other (and move more slowly) than in gases. For this reasons, the particles have higher chances of collision, and since conduction is the transfer of energy via collisions of the particles, conduction occurs more easily in solids and liquids than in gases.