**Core Concept**
The triangle of auscultation is an anatomical region on the back, bounded by three muscles: latissimus dorsi, trapezius, and rhomboid major. This region is clinically significant for auscultation of sounds from the lungs and heart.

**Why the Correct Answer is Right**
The correct answer should be a muscle that does not form the boundary of the triangle of auscultation. The latissimus dorsi muscle forms the base of the triangle, the trapezius muscle forms the upper boundary, and the rhomboid major muscle forms the lower boundary. The levator scapulae muscle is not one of the boundaries.

**Why Each Wrong Option is Incorrect**
**Option A:** The latissimus dorsi muscle is one of the boundaries of the triangle of auscultation.
**Option B:** The trapezius muscle is one of the boundaries of the triangle of auscultation.
**Option C:** The rhomboid major muscle is one of the boundaries of the triangle of auscultation.

**Clinical Pearl / High-Yield Fact**
The triangle of auscultation is a useful landmark for physicians to identify during physical examination, particularly when auscultating lung and heart sounds. The boundaries of this triangle should be remembered to avoid confusion with other anatomical regions.

**Correct Answer:** D. Levator scapulae muscle.