**Core Concept**
Cerebral palsy is a group of permanent disorders appearing in early childhood, characterized by **developmental delay**, **impairment of motor function**, and **limitation of activity**. Spastic diplegia is a subtype of cerebral palsy, primarily affecting the **lower limbs**. The severity of affection in limbs varies among individuals.

**Why the Correct Answer is Right**
Since the correct answer is not provided, let's discuss the general understanding of spastic diplegia. In spastic diplegia, the **lower limbs** are more severely affected than the **upper limbs**, with **spasticity** and **weakness** being prominent features. This is due to the **periventricular leukomalacia**, which is a form of **white matter brain injury** commonly associated with spastic diplegia.

**Why Each Wrong Option is Incorrect**
**Option A:** Without the specific details of option A, we cannot comment on its accuracy.
**Option B:** Similarly, without the details of option B, its correctness cannot be assessed.
**Option C:** The same applies to option C, as the specific content is not provided.
**Option D:** Option D's accuracy also cannot be determined without its content.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that spastic diplegia primarily affects the **lower limbs**, with the **upper limbs** being less involved or sometimes appearing nearly normal. This is a crucial distinction in diagnosing and managing cerebral palsy.

**Correct Answer:** Correct Answer: D. Lower limbs more than upper limbs.