The answer is D. This is referred to as reflex reaction. Reflex is the instantaneous and involuntary reactions to a stimuli. Reflex arc does not pass through the brain so the reaction time is shorter than normal. This is a adaptation to increase survival.
Answer: As altitude increases, the spacing between particles increase.
Explanation: There is less gravity when altitude increases to compact the particles together and particles are more free flowing to move around. Therefore the particles aren't as close together, increasing the amount of space in between them.
Seafloor spreading is the answer
