Step 1: Understanding the Calculation.
The weight/volume percentage is calculated using the formula:
\[
\text{W/V} % = \frac{\text{Weight of solute (g)}}{\text{Volume of solution (mL)}} \times 100
\]
Step 2: Calculation.
- The concentration is 1.2% W/V NaCl, so for every 100 mL of solution, we have 1.2 grams of NaCl.
- Therefore, the correct answer is (B) 1.2% W/V NaCl.