Plants such as the cactus reside in the desert biome.
In an experiment, that subjected participants to increasing isolation in a computerized ball-tossing game, fMRI scans showed activity in the cingulate cortex, a region of the brain that is active during EMOTIONAL PAIN.
Cingulate cortex is the limbic lobe involved in emotion formation, memory, learning, problem solving and self control.
I am thinking the rock that forms from lava that cools quickly is D) Obsidian.
Well, think of it this way.
When you do not eat that much, your body fat lowers little by little, but considering that this is a question, I'd say starvation. Think of it as when you fast (Not eating all night say to go to a doctors appointment) your body stores the fatty acids to make ketone! The ketone will build a bloodstream that flows to the brain and other parts of the body!
To sum it up, starvation.
