Which of the following statements are not correct in reference to hydroponics?
$I.$ It determines the mineral nutrients essential for the plants.
$II.$ The hydroponics involves the culture of plants in a soil with,defined mineral solution.
$III.$ Hydroponics requires purified water with non-defined mineral nutrient salts.
$IV.$ In the hydroponics technique,plants are grown in sandy soil with nutrient solution.
$V.$ By this method,essential elements required for the growth of plants can be identified and their deficiency symptoms can also be discovered.
Choose the correct options.

• A
  Only $IV$
• B
  Only $V$
• C
  Only $III$
• D
  $II, III, IV$