question_answer

Consider the following statements:

1. Ocean crusts are denser than the continental crust.

2. Oceanic crusts are made up of granitic rocks whose composition is silicon and aluminium.

3. Granitic rocks are lighter in colour than basaltic.

4. Crust extends upto 70 km under mountains, in contrast to oceans which are about 5 km.

Which of the above statements are true?

A)  1, 3 and 4                         

B)  1, 2 and 4

C)  2, 3 and 4             

D)  1, 2, 3 and 4