Which animal lays the largest egg?

Birds are egg-laying vertebrates adapted for flying.  

Ostrich is a flightless bird that lays the largest eggs. The egg of an ostrich measures approximately 15 cm long and 13 cm wide. They weigh nearly 1.5 Kg and require about 50 minutes to boil it. 

Elephants and whales are mammals that give birth to living young ones, while the dinosaur is an extinct reptile.