Which of the following substances will change the colour of methyl orange indicator to yellow?
Window cleaner (ii) Vinegar (iii) Apple juice (iv) Washing soda (v) Caustic soda (vi) Carbonic acid (vii) Citric acid

Options

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

Explanation

To determine which substances will change the color of the methyl orange indicator to yellow, we need to identify which of the given substances are basic. Methyl orange is an acid-base indicator that turns red in acidic solutions and yellow in basic solutions.

### Step-by-Step Solution:

1. **Understand Methyl Orange Indicator**:
- Methyl orange is a pH indicator that changes color based on the acidity or basicity of a solution. It turns red in acidic conditions (pH < 3.1) and yellow in basic conditions (pH > 4.4).

2. **List the Given Substances**:
- (i) Window cleaner
- (ii) Vinegar
- (iii) Apple juice
- (iv) Washing soda
- (v) Caustic soda
- (vi) Carbonic acid
- (vii) Citric acid

3. **Identify the Nature of Each Substance**:
- **Window Cleaner**: Generally contains ammonia or other basic compounds, making it basic.
- **Vinegar**: Contains acetic acid, making it acidic.
- **Apple Juice**: Contains natural acids, making it acidic.
- **Washing Soda (Sodium Carbonate)**: Basic in nature (Na2CO3).
- **Caustic Soda (Sodium Hydroxide)**: Strongly basic (NaOH).
- **Carbonic Acid**: Weak acid (H2CO3), making it acidic.
- **Citric Acid**: Weak acid (C6H8O7), making it acidic.

4. **Determine Which Substances are Basic**:
- From the analysis:
- Window Cleaner: Basic
- Washing Soda: Basic
- Caustic Soda: Basic
- Vinegar: Acidic
- Apple Juice: Acidic
- Carbonic Acid: Acidic
- Citric Acid: Acidic

5. **Conclusion**:
- The substances that will change the color of methyl orange to yellow (indicating a basic solution) are:
- Window Cleaner
- Washing Soda
- Caustic Soda

### Final Answer:
The substances that will change the color of methyl orange indicator to yellow are:
- Window Cleaner
- Washing Soda
- Caustic Soda