A fire work gives out crimson coloured light. It contains the salt of

Options

A. calcium
B. sodium
C. barium
D. strontium

Explanation

To determine which salt is responsible for the crimson-colored light emitted by fireworks, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Fireworks and Color Emission**: Fireworks produce different colors based on the metal salts they contain. Each metal salt emits a characteristic color when heated.

2. **Identifying the Color**: The question specifies that the firework emits a crimson (red) colored light. We need to find out which metal salt is known to produce this color.

3. **Researching Metal Salts**: Among the common metal salts used in fireworks, we can consider:
- Strontium compounds (like strontium carbonate)
- Lithium compounds (like lithium carbonate)
- Calcium compounds (like calcium salts)
- Barium compounds (like barium salts)

4. **Color Association with Metal Salts**:
- Strontium salts are known to produce a crimson or red flame.
- Lithium salts produce a bright red flame, but they are not specifically referred to as crimson.
- Calcium salts typically give an orange-red color.
- Barium salts produce a green color.

5. **Conclusion**: Given that strontium salts are specifically known for producing a crimson red color, we can conclude that the firework containing the salt of strontium is responsible for the crimson-colored light.

### Final Answer:
The firework that gives out crimson colored light contains the salt of **Strontium**.

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