How do organisms acquire the energy they need to live?

organisms generate their own energy to live.
organisms capture energy from the environment.
organisms acquire energy from hydrolysis.
organisms acquire energy from the temperature of the earth.

The serengeti plains are part of the african savanna ecosystem and are home to a variety of different species of plants and animals. the serengeti plains experience a seven-month period of seasonal drought each year, during which the ecosystem receives only four inches of rain and the availability of some resources becomes very scarce. which type of limiting factors does the seasonal drought in the serengeti plains affect?