Question

The following substances are the excretory products in animals. Choose the least toxic form among them?

Answer 1

Urea

Urea is less toxic than ammonia, and can be stored for longer in the body. Water loss from the body is less through excretion.

Uric acid

Uric acid is least toxic. Hence, uricotelic animals store them in their body for a long time and excrete in a more concentrated form.

Ammonia

Ammonia is highly toxic and requires a large amount of water for its removal through excretion.

Carbon dioxide

Carbon dioxide is excreted out through lungs. It's not a nitrogenous waste.

Final answer
option(b) Uric acid