**Core Concept**
The question is testing the understanding of the role of antibiotics in preventing or reducing the risk of complications in a child with sore throat and high-grade fever. The key concept here is the use of antibiotics in reducing the risk of post-streptococcal complications.

**Why the Correct Answer is Right**
The correct answer is related to the fact that antibiotics are effective in reducing the risk of post-streptococcal complications such as acute rheumatic fever (ARF) and post-streptococcal glomerulonephritis (PSGN) when started promptly within the first 9-10 days of sore throat symptoms. This is because antibiotics can reduce the bacterial load and prevent the spread of Group A beta-hemolytic Streptococcus (GABHS) to other parts of the body.

**Why Each Wrong Option is Incorrect**
* **Option A:** Incorrect because antibiotics can reduce the risk of ARF and PSGN.
* **Option B:** Incorrect because antibiotics can reduce the risk of PSGN.
* **Option C:** Incorrect because antibiotics can reduce the risk of ARF.

**Clinical Pearl / High-Yield Fact**
It is essential to note that antibiotics do not reduce the duration of symptoms or the severity of sore throat, but they can reduce the risk of post-streptococcal complications when started promptly.

**Correct Answer:** D.