I believe the answer to this is C. Because A B and D can be treated and cured with Pancreatic cancer you can cure it.
They do not influence the salinity level in their environment, they maintain the salinity in their body. If they don't, osmosis will cause their cells to shrink due to the fact that the salinity in the cell is lower than outside the cell. This will make water leave the cells. So they need to get rid of excess salt all the time. Freshwater fish need to retain the salt in their bodies, otherwise the opposite will happen. Salinity level in the cell is higher than outside the cell and this causes influx of water which will make the cell build up turgor pressure. Ultimately they will explode. So fishes in both environments adapted to deal with osmosis.
Cellular respiration depends on two chemical reactants; glucose and oxygen. Glucose and oxygen are made available to plants and animals for cellular respiration thanks to photosynthesis. Photosynthesis is the chemical reaction that uses solar energy to convert water and carbon dioxide into glucose and oxygen. Without photosynthesis, the available glucose and oxygen on the planet would quickly deplete to the point that life could not be sustained on Earth.
