**Core Concept**
Intraoral periapical radiographs are a common diagnostic tool in dental and maxillofacial radiology, utilizing X-rays to produce images of teeth and surrounding bone. The mean exposure of radiation from these radiographs is essential to consider due to the potential risks associated with long-term radiation exposure.

**Why the Correct Answer is Right**
The correct answer is **0.07 millisieverts (mSv)**. This is because the mean exposure of radiation from a single intraoral periapical radiograph is typically around 0.07 mSv, which is relatively low compared to other medical imaging modalities. The low dose is due to the use of a small X-ray beam and the collimation of the beam to the specific area of interest, minimizing exposure to surrounding tissues.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it is significantly higher than the actual mean exposure of radiation from an intraoral periapical radiograph.
* **Option B:** This option is incorrect because it is lower than the actual mean exposure of radiation from an intraoral periapical radiograph, which is not consistent with the typical radiation doses used in dental radiography.
* **Option D:** This option is incorrect because it is not a commonly used unit of measurement for radiation exposure in this context.

**Clinical Pearl / High-Yield Fact**
It is essential for dental professionals to minimize radiation exposure to patients by using the lowest possible dose necessary to produce diagnostic images, following the ALARA principle (As Low As Reasonably Achievable).

**Correct Answer:** C. 0.07 millisieverts (mSv)