Which activity is most likely a result of a sudden unexpected change in the environment

Usually when speaking about a sudden change in the environment many things can happen. for example a species could potentially die off (extinction) because they are not able to keep up with the change. in other words, if a climate suddenly goes from very warm and humid to dry and cold the animal that is used to the humidity will die because the makeup of its genes are not able to withstand the drastic change in its environment. hopefully this answers your question!