**Core Concept**
Sensory neurons, also known as afferent neurons, play a crucial role in transmitting sensory information from sensory receptors to the central nervous system. They are specialized to detect and respond to various stimuli such as light, sound, touch, taste, and smell.

**Why the Correct Answer is Right**
Sensory neurons have a distinct structure that allows them to perform their function. They typically have a large dendritic tree, a long axon, and a small or absent cell body. The dendrites of sensory neurons receive synaptic inputs from sensory receptors, while the axon transmits the signals to the central nervous system. The structure of sensory neurons enables them to detect and encode sensory information efficiently.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not describe the structure of sensory neurons. Motor neurons, which are involved in transmitting signals from the central nervous system to muscles and glands, have a different structure.
**Option B:** This option is incorrect because it describes the structure of interneurons, which are involved in processing and integrating information within the central nervous system. Interneurons have a different structure than sensory neurons.
**Option C:** This option is incorrect because it describes the structure of Purkinje cells, which are a type of neuron found in the cerebellum. Purkinje cells have a large dendritic tree and a long axon, but they are involved in motor coordination and learning, not sensory processing.

**Clinical Pearl / High-Yield Fact**
It's essential to remember that sensory neurons are responsible for transmitting sensory information from the peripheral nervous system to the central nervous system. This process is critical for our perception of the environment and our ability to respond to various stimuli.

**Correct Answer: A. Unipolar neurons**