Consider the following statements:

1.Atolls are low islands found in all the oceans consisting of coral reefs surrounding a central depression.

2.Guyot is a mountain with pointed summit, rising from the seafloor that does not reach the surface of the ocean.

3.Submarine canyons are deep valleys in the ocean floor. Hudson canyon is the best known submarine canyon in the world.

Which of the statements given above is/are correct?