The characteristic property of detergent :  

Options

A. is it contains both hydrophilic and hydrophobic groups
B. is it can act as an emulsifier
C. is it enables water and oily substances to form emulsions
D. all the above

Answer

To determine the characteristic properties of detergents, we will analyze each of the given options step by step.

### Step 1: Analyze the first option
**Statement:** It contains both hydrophilic and hydrophobic groups.

**Explanation:** Detergents are amphiphilic molecules, meaning they have both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts. This property allows them to interact with both water and oils, making them effective in cleaning.

**Conclusion:** This statement is true.

### Step 2: Analyze the second option
**Statement:** It can act as an emulsifier.

**Explanation:** An emulsifier is a substance that helps to stabilize emulsions, which are mixtures of two immiscible liquids, such as oil and water. Detergents can reduce the surface tension between these liquids, allowing them to mix more easily and remain stable.

**Conclusion:** This statement is also true.

### Step 3: Analyze the third option
**Statement:** Enables water and oily substances to form emulsions.

**Explanation:** Detergents facilitate the mixing of water and oils, which typically do not mix well. By surrounding oil droplets with their hydrophobic tails and their hydrophilic heads facing the water, detergents allow these two substances to form stable emulsions.

**Conclusion:** This statement is true as well.

### Step 4: Analyze the fourth option
**Statement:** All of the above.

**Explanation:** Since all the previous statements have been confirmed as true, it follows that the fourth option, which states that all the previous properties are characteristic of detergents, is also true.

**Conclusion:** The correct answer is "All of the above."

### Final Answer:
The characteristic property of detergents is that they contain both hydrophilic and hydrophobic groups, can act as emulsifiers, and enable water and oily substances to form emulsions. Therefore, the answer is **all of the above**.

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