**Core Concept**
Nursing bottle syndrome, also known as early childhood caries, is a condition characterized by rapid progression of dental caries in infants and young children due to prolonged exposure to sugary substances, often through a bottle or breast. The primary reason for replacing teeth destroyed in this condition is to restore oral function, aesthetics, and prevent further complications such as malocclusion, speech difficulties, and social embarrassment.

**Why the Correct Answer is Right**
The correct answer is related to the goal of replacing teeth destroyed due to nursing bottle syndrome. The primary reason is to restore the patient's oral function, which includes proper chewing and speaking. Since the affected teeth are often severely decayed and cannot be restored, they need to be replaced with artificial teeth such as crowns, bridges, or dentures. This is a crucial step in preventing further complications and improving the patient's quality of life.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because while oral hygiene is an essential aspect of preventing dental caries, it is not the primary reason for replacing teeth destroyed due to nursing bottle syndrome.

**Option B:** This option is incorrect because while diet modification is crucial in preventing dental caries, it is not the primary reason for replacing teeth destroyed due to nursing bottle syndrome.

**Option C:** This option is incorrect because while oral surgery may be necessary in some cases, it is not the primary reason for replacing teeth destroyed due to nursing bottle syndrome.

**Clinical Pearl / High-Yield Fact**
It is essential for pediatric dentists and primary care physicians to educate parents and caregivers about the risks of nursing bottle syndrome and the importance of proper oral hygiene, diet, and regular dental check-ups to prevent this condition.

**Correct Answer:** D.