The right answer is the activation energy.
The catalyst increases the reaction rate by introducing new reaction paths (mechanism), and lowering its activation energy, or activation Gibbs free energy. By doing this it can increase the speed, or lower the temperature of the reaction. It is important to note that the catalyst does not alter the total Gibbs free energy of the reaction which is a system state function and therefore has no effect on the equilibrium constant.
C- Single-celled organisms and soft, boneless animals.
It’s a simple thing really, the more options or “diversity” it’s more likely that it will be more sustainable and things will find a way to survive. Think about it like a video game level, the more tries you have the more likely you are for success