Which one of these is a component you will NOT find in any water filters?

Options

A. Activated charcoal
B. Ceramic candles
C. Ultraviolet rays
D. Alum

Explanation

To determine which component is NOT found in any water filters, we can analyze the options provided:

### Step 1: Identify the components listed
The options given are:
1. Activated charcoal
2. Ceramic candles
3. Ultraviolet rays
4. Alum

### Step 2: Understand the function of each component
- **Activated Charcoal**: This is commonly used in water filters to adsorb impurities, dirt, and harmful substances from water, making it cleaner and safer to drink.

- **Ceramic Candles**: These are also used in water filtration systems. They work by trapping dirt and bacteria, ensuring that the water is purified.

- **Ultraviolet Rays**: UV light is used in some water purification systems to kill bacteria and viruses, making the water safe for consumption.

- **Alum**: This is a chemical compound that is used in some water treatment processes but is not typically used in standard water filters. It can cause coagulation of impurities but is not a filtering component itself.

### Step 3: Determine which component is not used in water filters
From the analysis:
- Activated charcoal, ceramic candles, and ultraviolet rays are all components found in water filters.
- Alum, while it can be involved in water treatment, is not a component you would find in a water filter designed for household use.

### Conclusion
The component you will NOT find in any water filters is **Alum**.

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