Select the option which arranges the following steps in a correct sequence as per Gram's staining technique :
Treatment with `0.5 %` iodine solution (1), washing with water (2), treatment with absolute alcohol/acetone (3), staining with weak alkaline solution of crystal violet (4).

Options

A. `4rarr1rarr2rarr3`
B. `3rarr2rarr1rarr4`
C. `3rarr1rarr2rarr4`
D. `4rarr2rarr3rarr1`

Explanation

To solve the question regarding the correct sequence of steps in Gram's staining technique, we will follow the steps outlined in the video transcript and arrange them properly.

### Step-by-Step Solution:

1. **Staining with Weak Alkaline Solution of Crystal Violet (Step 4)**:
- The first step in the Gram staining process is to stain the bacteria with a weak alkaline solution of crystal violet. This dye is the primary stain that colors the bacterial cells.

2. **Treatment with 0.5% Iodine Solution (Step 1)**:
- After staining, the next step is to treat the stained bacteria with a 0.5% iodine solution. Iodine acts as a mordant, which helps to fix the crystal violet dye to the bacterial cells.

3. **Washing with Water (Step 2)**:
- The third step is to wash the bacteria with water. This step removes any excess iodine and unbound dye, ensuring that only the dye that is fixed to the cells remains.

4. **Treatment with Absolute Alcohol/Acetone (Step 3)**:
- Finally, the last step is to treat the cells with absolute alcohol or acetone. This step decolorizes the cells, allowing differentiation between Gram-positive and Gram-negative bacteria. Gram-positive bacteria will retain the crystal violet stain, while Gram-negative bacteria will lose it.

### Correct Sequence:
Thus, the correct order of steps in Gram's staining technique is:
- **4 (Staining with crystal violet) → 1 (Treatment with iodine) → 2 (Washing with water) → 3 (Treatment with alcohol/acetone)**.

### Answer:
The correct option is **4 → 1 → 2 → 3**.

---