**Core Concept**
Prolonged thumb sucking is a habit that can lead to various dental and skeletal abnormalities in children due to the constant pressure exerted on the upper jaw and teeth. This habit affects the growth and development of the maxilla and can lead to malocclusion.

**Why the Correct Answer is Right**
The correct answer is related to the effects of prolonged thumb sucking on the dental and skeletal structures. Thumb sucking can cause the upper incisors to be protruded, the upper central incisors to be spaced apart, and the upper jaw to be narrow. Additionally, it can also lead to a Class II malocclusion. The constant pressure exerted on the upper jaw can also cause the maxilla to be underdeveloped, leading to a narrow upper jaw.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because prolonged thumb sucking can indeed cause an open bite, which is a type of malocclusion where the upper and lower teeth do not meet when the mouth is closed.
**Option B:** This option is incorrect because prolonged thumb sucking can lead to a narrow upper jaw, not a wide one.
**Option C:** This option is incorrect because prolonged thumb sucking can cause the upper incisors to be protruded, not receded.

**Clinical Pearl / High-Yield Fact**
It's essential to note that prolonged thumb sucking can have long-term effects on the dental and skeletal development of children. Early intervention and treatment by an orthodontist or pediatric dentist can help mitigate these effects.

**Correct Answer: C. Protruded upper incisors.**