Okay, let's tackle this question about the Glasgow Coma Scale (GCS) score for a conscious person. First, I need to remember what the GCS entails. The GCS assesses three components: eye opening, verbal response, and motor response. Each component has a score range, and the total score is the sum.

A conscious person should have the highest possible scores in all three categories. For eye opening, the maximum is 4 (spontaneous). Verbal response for an oriented person is 5. Motor response for obeying commands is 6. So adding those up gives 15. That's the maximum score, indicating full consciousness.

Now, the options aren't provided, but common distractors might include lower scores like 14 or 13. Let's think about why those are wrong. If someone has a score of 14, maybe they have a slight issue in one category, like a verbal score of 4. But a fully conscious person should have all 5 in verbal. A score of 13 could mean a motor score of 5, but again, a conscious person should have 6 in motor. Lower scores like 8 or below indicate coma. So options that are lower than 15 are incorrect because they don't reflect full consciousness.

Clinical pearl: The GCS is a critical tool in assessing consciousness levels. The maximum score is 15, and anything below 8 indicates a coma. Students should remember the three components and their maximums to avoid confusion. Also, knowing that a score of 15 means the patient is fully conscious is key for exams.

**Core Concept**
The Glasgow Coma Scale (GCS) quantifies consciousness based on three components: eye opening (E), verbal response (V), and motor response (M). A fully conscious individual achieves the maximum score in each category.

**Why the Correct Answer is Right**
A conscious person scores **E4** (spontaneous eye opening), **V5** (oriented and coherent speech), and **M6** (obeys commands). Summing these yields a total of **15**, the highest possible score on the GCS. This reflects intact neurological function without deficits.

**Why Each Wrong Option is Incorrect**
**Option A:** A score of 14 implies a deficit in one component (e.g., V4 due to confusion).
**Option B:** A score of 13 suggests a moderate deficit (e.g., M5 due to abnormal flexion).
**Option C:** A score of 8 or below indicates coma, not consciousness.

**Clinical Pearl / High-Yield Fact**
The GCS is a cornerstone in neurotrauma and ICU settings. A score of 15 means *no coma*, while ≤8 defines coma. Memorize the maximums: **E4 + V5 + M6 = 15**.

**Correct Answer: D. 15**

✓ Correct Answer: D. 15