**Core Concept**
The question tests the knowledge of physical properties of dental materials, specifically condensation silicone, a type of elastomeric impression material. This material is used for taking accurate impressions of the oral cavity, allowing for the fabrication of dental restorations, such as metal ceramic crowns.

**Why the Correct Answer is Right**
Condensation silicone impression materials have a unique set of physical properties that make them suitable for dental impressions. The mean working time and mean setting time of these materials are critical factors in determining their usability. The working time is the duration during which the material can be mixed and manipulated before it starts to set, while the setting time is the duration required for the material to reach its final set state. The correct answer for the mean working time of condensation silicone is typically around **4-6 minutes**, and the mean setting time is around **4-6 minutes** as well. This allows the dentist to mix the material, place it in the mouth, and remove it before it sets, resulting in an accurate impression.

**Why Each Wrong Option is Incorrect**
**Option A:** The mean working time and mean setting time of condensation silicone are not typically **2-4 minutes**. This is shorter than the actual working time and setting time, which would not provide enough time for the dentist to mix and place the material.
**Option B:** The mean working time and mean setting time of condensation silicone are not typically **6-8 minutes**. This is longer than the actual working time and setting time, which would not be practical for most dental procedures.
**Option C:** The mean working time and mean setting time of condensation silicone are not typically **1-3 minutes**. This is too short and not representative of the actual working time and setting time of condensation silicone.

**Clinical Pearl / High-Yield Fact**
It's essential to note that the physical properties of dental materials, including condensation silicone, can be affected by factors such as temperature, humidity, and mixing technique. Dentists should always follow the manufacturer's instructions and take into account the specific conditions of the dental procedure when selecting and using dental materials.

**Correct Answer:** D.