I believe the answer is B. Heart
The tilt of the Earth is what causes the seasons...In the summer, the northern pole is pointed closer to the Sun giving the northern hemisphere more daylight hours. The opposite is true during the winter.
The movement of water molecules in and out of a cell is called osmosis.
Osmosis, or the diffusion of water molecules, is when water molecules flow in or out of a cell from high to low concentrations (down their concentration gradient). The ultimate goal of osmosis is to establish equilibrium between the cell and its outer environment.
Hope this helps!
To perform this test to check if gold is real, make a light, tiny scratch on the item using a small nail file. Choose a spot that is not noticeable if possible. Use a dropper to apply a small drop of nitric acid to the scratch. If there is no reaction, then the piece is probably made from real gold.
I believe that would be irritability.