For number one, wolves may eat fish instead of larger animals because those larger animals may be going into hibernation and also the berries that a wolf may eat has also gone out of season, leaving the only choice really being fish.
For number two, over harvesting salmon is pretty bad when it comes to the environment. it takes away food from predators, like the wolves in number one, so they lose a source of food and it also takes away the salmons ability to eat the smaller organisms in the stream, so they're going to become overpopulated.
The best answer is (1)
Fossil fuels are commercially available as an energy source.
They are very easy to find. More and more extractions of fossil fuels is going on everyday. With advancement in science and technology, the refineries and extraction procedures have improved a lot. This makes their availability even better.
Fossil fuels are also easily combustible. Most combustion engines need to be powered with little amount of fuel to produce large amount of energy. Very large amounts of electricity can be generated from fossil fuels.
monosaccharides, disaccharides, polysaccharides
The monomer of carbohydrates, monosaccharides.
