Microelements are those nutrients which

Options

A. may not be essential
B. may be essential
C. are not essential and required in traces
D. are essential and required in traces.

Answer

**Step-by-Step Solution:**

1. **Definition of Microelements**: Microelements, also known as trace elements, are nutrients that are required by living organisms in very small amounts.

2. **Essentiality**: Microelements can be classified as essential or non-essential. However, in the context of biological functions, many microelements are considered essential for various physiological processes.

3. **Requirement in Traces**: The defining characteristic of microelements is that they are required in trace amounts. This means that the body needs them in very small quantities compared to macronutrients.

4. **Functionality**: Despite being needed in small amounts, microelements play crucial roles in the body's functioning. They are involved in various biochemical processes and are vital for maintaining health.

5. **Conclusion**: Therefore, the correct statement regarding microelements is that they are nutrients which are essential and required in traces.

**Final Answer**: Microelements are those nutrients which are essential and required in traces.

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