a plant is a kind of organism & crops are a kind of edible plant for eating ->  a crop is a kind of organism  a organisms require water for survival / to grow & water is a kind of natural resource ->  water is a kind of natural resource that organisms require to survive  water is a kind of natural resource that organisms require to survive & when available resources decrease in an environment , organisms have to conserve those resources ->  when water decreases in an environment, organisms have to conserve water to survive  when water decreases in an environment, organisms have to conserve water to survive & drought is when available water decreases in an environment ->  organisms have to conserve water to survive in a drought  a crop is a kind of organism & organisms have to conserve water to survive in a drought & if a crop requires less water then that crop will survive in a drought ->  crops that survive in droughts can conserve water  crops that survive in droughts can conserve water & planting crops is a kind of activity -> planting crops that survive in droughts is a kind of activity that conserves water