Consider the following statements. 

I. Diatom is porous and chemically inert. It is therefore, used in filtration of sugars, alcohols, oils, syrups and antibiotics.

II. Diatomite deposits are often formed after death of diatoms. 

III. Desmids along with diatoms are the chief producers. 

Which of the statements given above are correct? 

• A

  I and II 

• B

  I and III 

• C

  II and III 

• D

  I, II and III