**Core Concept**
The process of releasing chemicals from nerve terminals is known as neurotransmission, a crucial mechanism for transmitting signals between neurons and other cells. This process involves the release of neurotransmitters, which are chemical messengers that facilitate communication between neurons.

**Why the Correct Answer is Right**
The discovery of neurotransmission is attributed to Otto Loewi, who demonstrated that the vagus nerve releases a chemical that slows the heart rate. He isolated the chemical, which he called vagus substance, and later identified it as acetylcholine. Loewi's work laid the foundation for our understanding of neurotransmitters and their role in neural communication. The release of neurotransmitters from nerve terminals is a complex process that involves the fusion of vesicles containing neurotransmitters with the presynaptic membrane, releasing the neurotransmitters into the synaptic cleft.

**Why Each Wrong Option is Incorrect**
**Option A:**
This option is incorrect because it does not mention the correct researcher who discovered the process of neurotransmission. While Pavlov's work on classical conditioning was groundbreaking, it did not involve the discovery of neurotransmitters.

**Option B:**
This option is incorrect because it does not accurately describe the process of neurotransmission. Although the concept of "nerve terminals release chemicals" is correct, the specific researcher associated with this discovery is not mentioned.

**Option C:**
This option is incorrect because it does not mention the correct researcher who discovered the process of neurotransmission. While Cajal's work on neuron structure was influential, it did not involve the discovery of neurotransmitters.

**Clinical Pearl / High-Yield Fact**
One key takeaway from Loewi's discovery is that neurotransmitters play a crucial role in regulating various physiological processes, including heart rate, blood pressure, and muscle contraction. Understanding the mechanisms of neurotransmission is essential for developing effective treatments for neurological and psychiatric disorders.

**Correct Answer: C. Otto Loewi**