Read the following statements and identify the organism we are referring to:

(a) Cell walls form two thin overlapping shells.

(b) The walls are embedded with silica and thus the walls are indestructible.

(c) Chief ‘producers’ in the oceans

• A

  Diatoms

• B

  Dinoflagellates

• C

  Euglenoids

• D

  Slime moulds