Answer: Hypertonic solution
Explanation: In hypertonic solutions solute concentration is higher that those inside the cells. That means there is a different pressure in and out of the cell and in order to reach the equilibrium the cell has to release water to the medium and ever the concentration. As a result of this stressful conditions cells shrink which make pickles smaller.
A. lipids
There are different forms of lipids. The one described in the question is called triglyceride.
I thinks it's B. Molecular Receptor, but I am not sure.