Regeneration of anion exchange resin is carried out by passing

Options

A. sodium hydroxide solution
B. sodium chloride solution
C. sodium bicarbonate solution
D. All the above

Explanation

**Step-by-Step Solution:**

1. **Understanding Anion Exchange Resin:**
- Anion exchange resin is a type of ion exchange resin that is specifically designed to exchange negatively charged ions (anions) in a solution.

2. **Purpose of Regeneration:**
- Over time, the anion exchange resin becomes saturated with the anions it has absorbed from the water. To restore its effectiveness, the resin must be regenerated.

3. **Process of Regeneration:**
- The regeneration process involves passing a concentrated solution of a specific reagent through the resin. This reagent typically contains a high concentration of a particular anion that will displace the anions that are currently bound to the resin.

4. **Common Regeneration Reagents:**
- Common reagents used for the regeneration of anion exchange resins include sodium hydroxide (NaOH) or sodium chloride (NaCl). These reagents provide the necessary anions to replace the unwanted anions on the resin.

5. **Final Step:**
- After passing the regeneration solution through the resin, the resin is rinsed with water to remove excess reagent and any displaced anions, restoring its capacity to exchange anions effectively.