Which of the following elements is a macronutrient for higher plants and micronutrient for algae?

Options

A. Ca
B. Co
C. Cu
D. Cd

Answer

To solve the question "Which of the following elements is a macronutrient for higher plants and a micronutrient for algae?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand Macronutrients and Micronutrients**:
- Macronutrients are essential nutrients that plants require in large quantities for growth and development. Examples include nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur.
- Micronutrients are essential nutrients that are required in smaller amounts. Examples include iron, manganese, zinc, copper, molybdenum, boron, and chlorine.

2. **Identify the Elements**:
- From the question, we need to identify which element is categorized as a macronutrient for higher plants and a micronutrient for algae.

3. **Evaluate the Options**:
- We need to evaluate the provided options (not listed in the question but assumed to be present) to determine which element fits the criteria.
- For example, if the options include calcium, cobalt, cadmium, and copper, we analyze each:
- **Calcium**: Known to be a macronutrient for higher plants and can act as a micronutrient for some algae.
- **Cobalt**: Generally not classified as an essential nutrient for most plants or algae.
- **Cadmium**: Not an essential nutrient and can be toxic.
- **Copper**: Typically a micronutrient for both plants and algae.

4. **Conclusion**:
- Based on the analysis, **Calcium** is the element that serves as a macronutrient for higher plants and a micronutrient for algae.

### Final Answer:
The correct answer is **Calcium**.

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