The activities of man had adverse effects on all forms of living organisms in the biosphere. Unlimited exploitation of nature by man disturbed the delicate ecological balance between the living and non-living components of the biosphere. The unfavourable conditions created by man himself threatened the survival not only of him but also of the entire living organisms on the mother earth. One of your classmates is an active member of 'Eco club' of your school which is creating environmental awareness amongst the school students, spreading the same in the society and also working hard for preventing environmental degradation of the surroundings.
Which of these group(s) contains only non biodegradable items?
(i) Wood, paper, leather
(ii) Polythene, detergent, PVC
(iii) Plastic, detergent, grass
(iv) Plastic, bakelite, DDT

Options

A. (iii)
B. (iv)
C. (i) and (iii)
D. (ii) and (iv)

Explanation

To determine which group contains only non-biodegradable items, we need to analyze each option provided in the question.

### Step-by-Step Solution:

1. **Understanding Biodegradable vs Non-Biodegradable:**
- Biodegradable items are those that can be broken down naturally by microorganisms into simpler, harmless components.
- Non-biodegradable items cannot be decomposed naturally and remain in the environment for a long time.

2. **Analyzing Each Group:**
- **Group (i): Wood, Paper, Leather**
- Wood and paper are made from plant materials and are biodegradable.
- Leather, made from animal skin, is also biodegradable.
- **Conclusion:** This group is biodegradable.

- **Group (ii): Polythene, Detergent, PVC**
- Polythene (plastic) is non-biodegradable.
- Detergent is often non-biodegradable depending on its composition.
- PVC (Polyvinyl Chloride) is a type of plastic and is non-biodegradable.
- **Conclusion:** This group contains non-biodegradable items.

- **Group (iii): Plastic, Detergent, Grass**
- Plastic is non-biodegradable.
- Detergent is often non-biodegradable.
- Grass is biodegradable.
- **Conclusion:** This group is not entirely non-biodegradable.

- **Group (iv): Plastic, Bakelite, DDT**
- Plastic is non-biodegradable.
- Bakelite is a synthetic polymer and is non-biodegradable.
- DDT (Dichloro-Diphenyl-Trichloroethane) is a pesticide and is also non-biodegradable.
- **Conclusion:** This group contains only non-biodegradable items.

3. **Final Decision:**
- After analyzing all groups, we find that **Group (ii) and Group (iv)** contain only non-biodegradable items.
- However, since the question asks for a group containing only non-biodegradable items, the correct answer is **Group (iv): Plastic, Bakelite, DDT**.