I believe it is number 3.
Hope this helps!
Well depending on what the environmental change is the organisms will have to adapt, or move. if they don't they may not survive.
comment if you want an example or 2
Answer:
They may change due to environmental changes. for example, if a cactus suddenly experiences a drought, it may change to become better at holding water than before. if it suddenly experiences large amounts of rainfall, it may change to release more water, etc.
