**Core Concept**
Radiation exposure is a significant occupational hazard in the radiation industry. Replacement and periodic examination of radiation workers are essential to prevent long-term health effects, such as radiation-induced cancer and genetic damage.

**Why the Correct Answer is Right**
The correct answer is based on the concept of dose monitoring and radiation protection. Replacement and periodic examination help to prevent workers from accumulating high radiation doses, which can lead to deterministic effects like acute radiation syndrome. **Biological dosimetry**, using techniques like **chromosomal aberration analysis**, helps to assess individual radiation exposure and monitor the effectiveness of radiation protection measures.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not specify the type of examination or the frequency of replacement, which are crucial in radiation protection.
**Option B:** This option is incorrect as it only mentions replacement without considering the importance of periodic examination in monitoring radiation exposure.

**Clinical Pearl / High-Yield Fact**
The ALARA principle (As Low As Reasonably Achievable) is a fundamental concept in radiation protection, emphasizing the need to minimize radiation exposure to workers through regular monitoring and replacement.

**Correct Answer: D. Annual Chest X-ray and Periodic Medical Examination**