**Core Concept**
The underlying principle being tested is the normal EEG pattern in a awake individual with eyes closed, focusing on the **occipital region** of the brain. This region is primarily responsible for processing visual information. The **alpha rhythm** is a key concept here, typically seen in relaxed, awake individuals.

**Why the Correct Answer is Right**
When an individual is awake but relaxed with their eyes closed, the EEG typically shows an **alpha rhythm** at a frequency of 8-12 Hz. This rhythm is most prominently seen in the **occipital region**, which is involved in visual processing. The alpha rhythm is a result of the synchronized activity of **thalamocortical** neurons.

**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it does not specify the typical frequency range for the alpha rhythm.
**Option B:** Incorrect as it might refer to a different state or region of the brain.
**Option C:** Incorrect because it doesn't accurately describe the alpha rhythm's characteristics.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the **alpha rhythm** disappears when the individual opens their eyes, replaced by **beta waves** due to increased cortical activity. This change is a classic finding in EEG interpretations.

**Correct Answer:** D. Alpha waves