**Core Concept**
The World Health Organization's Oral Rehydration Solution (WHO-ORS) is a formulation of fluids used to treat dehydration caused by diarrhea. The new formula of WHO-ORS was introduced in 2002 to improve its efficacy and safety.

**Why the Correct Answer is Right**
The new formula of WHO-ORS contains reduced osmolarity, which means it has a lower concentration of salts compared to the original formula. This reduction in osmolarity helps to decrease the risk of hypernatremia and hyponatremia, making it safer for patients. The correct answer is the one that reflects this change in the WHO-ORS formula.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it mentions the original formula of WHO-ORS, which had a higher osmolarity and is no longer recommended.

**Option B:** This option is incorrect because it does not specify the reduction in osmolarity, which is the key feature of the new formula.

**Option C:** This option is incorrect because it mentions a different type of fluid replacement, such as intravenous fluids, which is not relevant to the new formula of WHO-ORS.

**Clinical Pearl / High-Yield Fact**
To remember the key feature of the new formula of WHO-ORS, recall the phrase "Reduce, Rehydrate, Recover," which reflects the reduction in osmolarity, the goal of rehydration, and the ultimate outcome of recovery.

**Correct Answer:** B. The new formula of WHO-ORS has a reduced osmolarity.