Question

Secondary nutrients in fertilizers are:

• A. boron, copper, manganese
• B. calcium, molybdenum, zinc
• C. iron, sulphur, molybdenum
• D. calcium, magnesium, sulphur

Hint:

Secondary nutrients in fertilizers include calcium, magnesium, and sulfur, which are essential for plant growth but required in smaller amounts.

Answer 1

The Correct Option is D

Step 1: Understanding secondary nutrients.
In fertilizers, secondary nutrients are nutrients that are essential for plant growth but required in smaller amounts than primary nutrients (nitrogen, phosphorus, potassium). Calcium, magnesium, and sulfur are considered secondary nutrients.

Step 2: Explanation of options.
- (D) Calcium, magnesium, and sulfur are indeed secondary nutrients in fertilizers. - (A), (B), and (C) These options refer to trace elements or micronutrients, not secondary nutrients.

Final Answer: \[ \boxed{\text{D) calcium, magnesium, sulphur}} \]