Elements causing deiayed flowering at low concentration are

Options

A. N, S, P
B. N, S, Mg
C. N, S, Mn
D. N, S, Mo

Answer

To solve the question regarding the elements causing delayed flowering at low concentrations, we can follow these steps:

### Step 1: Understand the Question
We need to identify which elements, when present in low concentrations, lead to delayed flowering in plants.

### Step 2: Analyze the Options
We have several elements to consider: nitrogen, sulfur, phosphorus, magnesium, manganese, and molybdenum. We need to evaluate each one based on its role in flowering.

### Step 3: Evaluate Each Element
1. **Nitrogen**:
- Nitrogen is essential for plant growth and development. An overabundance can delay flowering, while a deficiency can reduce yield. Thus, nitrogen can cause delayed flowering at low concentrations.

2. **Sulfur**:
- Sulfur is a structural component of amino acids and is necessary for chlorophyll production. Low sulfur levels can also delay flowering.

3. **Phosphorus**:
- Phosphorus is crucial for energy transfer and photosynthesis but does not directly influence flowering. Therefore, it is not involved in delayed flowering.

4. **Magnesium**:
- Magnesium is the central component of chlorophyll. While it is important for photosynthesis, it does not directly relate to flowering.

5. **Manganese**:
- Manganese is a micronutrient that plays a role in photosynthesis and metabolic processes but does not directly affect flowering.

6. **Molybdenum**:
- Molybdenum is involved in nitrogen metabolism and is crucial for the enzyme that converts nitrates to ammonia. Low levels can hinder protein synthesis and plant growth, potentially delaying flowering.

### Step 4: Identify the Correct Elements
From the evaluation, we find that nitrogen, sulfur, and molybdenum are the elements that can cause delayed flowering at low concentrations.

### Step 5: Conclusion
The correct answer to the question is that the elements causing delayed flowering at low concentrations are **nitrogen, sulfur, and molybdenum**.

### Final Answer
The elements causing delayed flowering at low concentrations are nitrogen, sulfur, and molybdenum.

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