I believe it is 4)Shearing teeth (Carnassial teeth)
Amniotic egg are for reptiles
Fur are for marsupials, and dogs
Retractable claws are are cats
Shearing teeth are for carnivores
It acts as a reactant in a chemical reaction.
Answer:
Nitrogen is a naturally occurring element that is essential for growth and reproduction in both plants and animals. It is found in amino acids that make up proteins, in nucleic acids, that comprise the hereditary material and life's blueprint for all cells, and in many other organic and inorganic compounds.
Explanation:
(I just copy and paste from google)
