Which of the following changes (i - vi) from the given list cannot be reversed?
(i) Breaking of an earthen pitcher (ii) Freezing of ice-cream (iii) Falling of trees during storm (iv) Filling of bucket with water (v) Rusting of a bicycle (vi) Digestion of food

Options

A. (i), (iii), (v) and (vi) only
B. (i), (iii) and (vi) only
C. (ii) and (iv) only
D. (v) and (vi) only

Explanation

To determine which of the changes listed cannot be reversed, we will analyze each option step by step.

### Step-by-Step Solution:

1. **Breaking of an earthen pitcher (i)**:
- When an earthen pitcher breaks, it shatters into pieces. Once broken, it cannot be restored to its original form.
- **Conclusion**: This is an irreversible change.

2. **Freezing of ice-cream (ii)**:
- Freezing ice-cream involves changing it from a liquid state to a solid state. However, once frozen, it can be melted back into a liquid.
- **Conclusion**: This is a reversible change.

3. **Falling of trees during a storm (iii)**:
- When trees fall due to a storm, they cannot be returned to their original position. The damage caused is permanent.
- **Conclusion**: This is an irreversible change.

4. **Filling of a bucket with water (iv)**:
- Filling a bucket with water can be reversed by emptying the bucket. The process can go back and forth.
- **Conclusion**: This is a reversible change.

5. **Rusting of a bicycle (v)**:
- Rusting is a chemical process where iron reacts with oxygen and moisture to form rust. Once rust forms, it cannot be easily converted back to iron.
- **Conclusion**: This is an irreversible change.

6. **Digestion of food (vi)**:
- Digestion involves breaking down food into simpler substances that the body can absorb. Once food is digested, it cannot be reverted back to its original form.
- **Conclusion**: This is an irreversible change.

### Summary of Irreversible Changes:
- Breaking of an earthen pitcher (i)
- Falling of trees during a storm (iii)
- Rusting of a bicycle (v)
- Digestion of food (vi)

### Final Answer:
The changes that cannot be reversed are (i), (iii), (v), and (vi).