**Core Concept**
The question is testing the knowledge of the transport mechanism of ammonia from muscles to the liver. Ammonia is a toxic compound that needs to be removed from the body, and the liver plays a crucial role in this process. The liver converts ammonia into urea, which is then excreted by the kidneys.

**Why the Correct Answer is Right**
The correct answer is glutamine, which is synthesized in the muscles and transports ammonia to the liver. This process is mediated by the enzyme glutamine synthetase, which catalyzes the reaction between glutamate and ammonia to form glutamine. The glutamine molecule is then transported to the liver, where it is deaminated by the enzyme glutaminase to release ammonia, which is then converted into urea.

**Why Each Wrong Option is Incorrect**
* **Option A:** Glucose is a simple sugar that does not play a role in ammonia transport.
* **Option B:** Lactate is a byproduct of anaerobic glycolysis and does not participate in ammonia transport.
* **Option C:** Alanine is an amino acid that can act as a gluconeogenic precursor, but it is not primarily involved in ammonia transport.

**Clinical Pearl / High-Yield Fact**
It's worth noting that the glutamine synthetase reaction is a critical step in ammonia detoxification, and defects in this enzyme can lead to hyperammonemia and neurological disorders.

**Correct Answer:** C. Alanine