**Core Concept**
The question tests the understanding of the **differential distribution of sensory nerve fibers** in the spinal nerves, specifically the difference in the distribution of tactile (light touch) and pain sensation fibers. This concept is rooted in **neuroanatomy** and **physiology of sensory pathways**.

**Why the Correct Answer is Right**
When a single spinal nerve is cut, the area of tactile loss is greater than the area of loss of painful sensations because of the way these sensations are mediated and the specificity of their pathways. Tactile sensation is primarily mediated by the dorsal column-medial lemniscus pathway, which is more segmentally specific, meaning that each spinal nerve carries tactile information from a specific dermatome. In contrast, pain sensation is mediated by both the lateral spinothalamic tract and, to some extent, the dorsal column-medial lemniscus pathway, with a less segmental specificity due to the convergence of pain fibers from multiple spinal segments.

**Why Each Wrong Option is Incorrect**
**Option A:** This option would be incorrect because it doesn't address the underlying reason for the difference in sensory loss areas.
**Option B:** Similarly, this option is incorrect as it doesn't provide a physiological basis for the observed phenomenon.
**Option C:** This option is also incorrect because it fails to consider the specific pathways involved in tactile and pain sensation.
**Option D:** This option does not accurately describe the relationship between the areas of tactile and pain sensation loss following a spinal nerve cut.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the **lateral spinothalamic tract**, which mediates pain and temperature sensation, has a more extensive overlap of dermatomes compared to the pathways for tactile sensation, leading to a smaller area of loss for pain sensation when a single spinal nerve is damaged.

**Correct Answer:** D. The area of tactile loss is always greater than the area of loss of painful sensations because pain sensation has a more extensive overlap of dermatomes due to the convergence of pain fibers in the spinal cord.