The living beings in an ecosystem are named biotic factors. Living beings involve plants, creatures, bacteria, parasites and many more. The non-living components of an ecosystem are named abiotic factors. In an ecosystem, few abiotic factors are sunshine, temperature, climatic gases, water, and clay.
Since we can't see your choices we can only do so much to help you unfortunately. However, the word abiotic means non living. So if it's saying which is NOT an example of an abiotic factor, then your answer would be the choice that has to do with living. For example, plants, animals, etc.
The kidneys is controlled by hormones and by the composition of the urine since the hormone released is called ADH which is produced by the pituitary gland.