First two don't make sense.
Third is correct.
Last one would be volume.
Answer:
Agricultural fertilizers are one of the main human causes of eutrophication. Fertilizers, used in farming to make soil more fertile, contain nitrogen and phosphorus. The use, or overuse, of fertilizers can cause these nutrients to runoff of the farmer's field and enter waterways. Eutrophication can have serious effects, like algal blooms that block light from getting into the water and harm the plants and animals that need it. If there's enough overgrowth of algae, it can prevent oxygen from getting into the water, making it hypoxic and creating a dead zone where no organisms can survive.
The following is a list of methods that can be used to control eutrophication:
planting vegetation along streambeds to slow erosion and absorb nutrients.
controlling application amount and timing of fertilizer.
controlling runoff from feedlots.
The best, easiest, and most efficient way to prevent eutrophication is by preventing excess nutrients from reaching water bodies. This can be done in a number of ways, the simplest of which is just being aware of the chemicals and fertilizers that we are using.
Passive transport means the cell does not have to spend energy to move gasses and fluids. the gasses or liquids go from a higher concentration to a place of lower concentration. Think about shaking a can of soda. There's a lot of pressure that builds up in the soda. When you open the soda, all of the pressure escapes to an area of lower pressure outside of the can. This is called diffusion. Osmosis is another form of passive transport. For example, in water osmosis, the water goes from a less salty solution to a more salty solution.
The correct answer is A. Diffusion and osmosis.
hope this helps =)