Select the correct combination of the statements $(i-iv)$ regarding the characteristics of certain organisms.
$(i)$ Methanogens are archaebacteria which produce methane in marshy areas.
$(ii)$ Nostoc is a filamentous blue-green alga which fixes atmospheric nitrogen.
$(iii)$ Chemosynthetic autotrophic bacteria synthesize cellulose from glucose.
$(iv)$ Mycoplasma lack a cell wall and can survive without oxygen.
The correct statements are:

• A
  $(ii)$ and $(iii)$
• B
  $(i), (ii)$ and $(iii)$
• C
  $(ii), (iii)$ and $(iv)$
• D
  $(i), (ii)$ and $(iv)$