`{:(,"Column A",,,"Column B"),(A.,"Potable water","( )",a.,"Electrolysis"),(B.,"Distilled water","( )",b.,"Irrigation"),(C.,"Acidulated water ","( )",c.,"Pure water"),(D.,"River water","( )",d.,"Laboratory purpose"),(,,"( )",e.,"Human consumption"):}`

Explanation

To match the items in Column A with those in Column B, we will analyze each item in Column A and find the most appropriate corresponding item in Column B based on their definitions and uses.

### Step 1: Analyze Potable Water
- **Potable Water**: This is water that is safe for human consumption.
- **Match**: It corresponds to **E. Human consumption**.

### Step 2: Analyze Distilled Water
- **Distilled Water**: This is water that has been purified through distillation, making it very pure and suitable for laboratory use.
- **Match**: It corresponds to **D. Laboratory purpose** and also relates to **C. Pure water** since distilled water is a type of pure water.

### Step 3: Analyze Acidulated Water
- **Acidulated Water**: This is water that has had an acid added to it, making it useful for certain chemical processes, particularly electrolysis.
- **Match**: It corresponds to **A. Electrolysis**.

### Step 4: Analyze River Water
- **River Water**: This is natural water found in rivers, which is often used for agricultural purposes.
- **Match**: It corresponds to **B. Irrigation**.

### Summary of Matches:
- A. Potable water → E. Human consumption
- B. Distilled water → D. Laboratory purpose
- C. Acidulated water → A. Electrolysis
- D. River water → B. Irrigation

### Final Matches:
- A - E
- B - D
- C - A
- D - B