Hard calcium carbonate structures are used as a skeleton by

State whether the following statement is true or false:
The plants of the $Angiosperm$ group bear naked seeds.

Find out the incorrect sentence.

Which one is the most striking or common character of the vertebrates?

How many chambers are present in the heart of fishes and frogs?

Classify the following animals based on the number of chambers in their heart: Rohu,Scoliodon,Frog,Salamander,Flying lizard,King Cobra,Crocodile,Ostrich,Pigeon,Bat,Whale.