Consider the following four statements $(A-D)$ and select the option which includes all the correct ones only.
$(A)$ Archaebacteria differ from other bacteria in having a different cell wall structure.
$(B)$ Bacteria as a group show the most extensive metabolic diversity.
$(C)$ All Eubacteria have chlorophyll ' $a$' pigment similar to green plants.
$(D)$ Mycoplasma can survive without oxygen.

• A
  Statements $B, C$ and $D$
• B
  Statements $A, C$ only
• C
  Statements $B, D$ only
• D
  Statements $A, B$ and $D$