Primary pollutants is the one, which

Options

A. Enters enviroment directly
B. Is formed naturally
C. Is byproducts of reactions between two or more pollutants components
D. Is anthropogenic .

Answer

**Step-by-Step Solution:**

1. **Understanding Primary Pollutants**:
- Primary pollutants are substances that are released directly into the environment in their harmful form. They do not require any transformation or reaction to become hazardous.

2. **Identifying Characteristics**:
- These pollutants are produced directly and can have immediate effects on health and the environment. Their presence, even in small amounts, can be undesirable and harmful.

3. **Evaluating Options**:
- The question provides several options regarding what primary pollutants are:
a) Enters environment directly
b) Formed naturally
c) Byproduct of reactions between two or more pollutants
d) Anthropogenic (human-made)

4. **Analyzing Each Option**:
- **Option a**: "Enters environment directly" - This aligns with the definition of primary pollutants.
- **Option b**: "Formed naturally" - While some primary pollutants can be natural (like volcanic ash), this does not define all primary pollutants.
- **Option c**: "Byproduct of reactions between two or more pollutants" - This describes secondary pollutants, not primary.
- **Option d**: "Anthropogenic" - While many primary pollutants are human-made, not all are; thus, this option is too narrow.

5. **Conclusion**:
- The best answer is **Option a: Enters environment directly**, as it accurately describes the nature of primary pollutants.