Whenever the sperm and the egg combine, it is possible for one or the other to not split properly and bring 2 of the chromosomes instead of just 1
Enzymes are biological catalysts. Catalysts work by lowering the amount of energy required to set off a chemical reaction.
Greenhouse gas emissions will continue to increase in the short term, but as new technologies are discovered and implemented by governments and industries, this may eventually reverse. Global climate may continue to warm, but once greenhouse gas emissions are lowered, this may slowly reverse. Current solutions are not yet enough to stop the increase in temperature, but some technologies on the horizon are promising, such as carbon capture and storage, solar energy, and aquaculture of biofuels. One immediate way to reduce greenhouse gas emissions is a change in lifestyle, for example, using less fuel-intensive transportation options and saving electricity.
The correct answer is C. humans
Language is an advanced system for communication available only to humans. Dolphins, chimps, and bees, use other means to communicate, but it is not a language, it's mostly things like smells or pheromones or similar things.