**Core Concept**
Clicking of denture during speaking is a common issue in denture wearers, primarily caused by the movement of the mandible (lower jaw) and the tension in the muscles of mastication (chewing). This problem is related to the temporomandibular joint (TMJ) and the surrounding muscles.

**Why the Correct Answer is Right**
The clicking sound is often due to an imbalance in the occlusion (the way the upper and lower teeth fit together) or a problem with the temporomandibular joint (TMJ). When the denture wearer speaks, the movement of the mandible can cause the TMJ to become misaligned, leading to the clicking sound. This is often due to a lack of posterior support or an overclosure of the mandible, which can be exacerbated by a poorly fitting denture.

**Why Each Wrong Option is Incorrect**
* **Option A:** This is not a recognized cause of clicking dentures. While it may be related to denture problems, it is not the primary cause.
* **Option B:** This is a possible cause of clicking dentures, but it is not the most common reason. A poorly fitting denture can indeed cause clicking, but it is often due to a more specific issue with the TMJ or occlusion.
* **Option D:** This is not a recognized cause of clicking dentures. While it may be related to denture problems, it is not the primary cause.

**Clinical Pearl / High-Yield Fact**
A poorly fitting denture can lead to a range of problems, including clicking, soreness, and difficulty speaking. It is essential to ensure a proper fit and occlusion to prevent these issues.

**Correct Answer: B. A poorly fitting denture can indeed cause clicking, but it is often due to a more specific issue with the TMJ or occlusion.**