Choose the correct statements with respect to kingdom Monera. 

I. They have simple structure.

II. They show extensive metabolic diversity.

III. Most of the monerans are autotrophic.

IV. Bacteria are grouped under four categories based on shape.

• A

  I and II only

• B

  II and III only

• C

  I, II and IV only

• D

  II, III and IV only