Concept:Kidneys are the main excretory organs in vertebrates.
Explanation:Fishes, amphibians, birds, and man are all vertebrates.
Vertebrates possess a pair of kidneys for excretion.
Annelids use nephridia, while insects use Malpighian tubules.
Tapeworms and protozoans do not have kidneys.
Therefore, only option A lists organisms that all use kidneys as excretory organs.
Answer:A. Fishes, amphibians, birds, man