Molybdenum compounds are used in

Options

A. Dye industry
B. For colouring leather
C. For colouring rubber
D. All of these

Explanation

To answer the question regarding the uses of molybdenum compounds, we will analyze the provided options step by step.

### Step 1: Identify the Uses of Molybdenum Compounds
Molybdenum compounds are known to have various applications in different industries. We need to determine the specific uses mentioned in the options.

### Step 2: Analyze Each Option
1. **Dye Industry**: Molybdenum compounds are indeed used in the dye industry for various applications, including coloring agents.
2. **Coloring Leather**: Molybdenum compounds can be used to enhance the color of leather products.
3. **Coloring Rubber**: Similarly, these compounds are also utilized in the rubber industry for coloring purposes.

### Step 3: Conclusion
Since molybdenum compounds are used in all the mentioned applications (dye industry, coloring leather, and coloring rubber), the correct answer is that they are used in all of these areas.

### Final Answer
The correct option is D: All of these.

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