Which of the following statements is true regarding the removal of impurities?
i. No filtration process is available to filter dissolved nitrates and phosphates
ii. Activated carbon filtration or aeration can filter trihalomethanes
iii. Fine sand filtration can filter coarse sand
iv. Precipitation with aluminum hydroxide can filter bacteria and finely divided particles

• A. i. & ii.
• B. i. & iv.
• C. ii. & iii.
• D. ii. & iv.

Answer: (D)