Respuesta :
Answer: Photosynthesis and cellular respiration.
Explanation:
In drought there is a scarcity of water and water being one of the most essential component of photosynthesis is necessary for the whole process to occur.
In case of water scarcity, the process of photosynthesis does not occurs properly. This leads to the reduced amount of production of oxygen in the environment.
Without adequate amount oxygen there is no oxygen available for the living things for cellular respiration.