Which of the following statements is true regarding Acanthamoeba keratitis?

• A. Keratitis due to Acanthamoeba is not seen in the immunocompromised host.
• B. Acanthamoeba does not depend upon a human host for the completion of its life-cycle.
• C. For the isolation of the causative agent,corneal scarping should be cultured on nutrient agar plate.
• D. The causative agent,Acanthamoeba is a helminth whose normal habitat is soil.