**Core Concept**
Autoclaving is a widely used method of sterilization that relies on high-pressure steam to achieve lethal temperatures. This process is crucial for eliminating bacterial, viral, and fungal contaminants from medical instruments and equipment.

**Why the Correct Answer is Right**
The correct answer involves exposure to 100°C for 20 minutes on 3 successive days. This specific protocol is a variation of a process known as "dry heat sterilization," but the description given in the question actually points towards a different method. The description given is more indicative of a process that does not rely on high pressure, which is characteristic of autoclaving. However, the temperature of 100°C for 20 minutes is still relatively high and indicative of dry heat sterilization.

The correct answer is actually a process called **tyndallization**. This process involves heating the material to 100°C for 20 minutes on 3 successive days. The first day's heating kills the most heat-resistant spores. The second day, the spores that were not killed on the first day are killed. The third day, any spores that were still alive are killed. This process ensures that the material is thoroughly sterilized.

**Why Each Wrong Option is Incorrect**

* **Option A:** Autoclaving typically involves exposure to high-pressure steam, which is not the case in the given description.
* **Option B:** Dry heat sterilization can involve temperatures higher than 100°C, but it is not typically done for 3 successive days.
* **Option C:** No information is provided to support this option as a correct method of sterilization.

**Clinical Pearl / High-Yield Fact**
Tyndallization is a method of sterilization that relies on the killing of microorganisms through heat, with each successive day of heating targeting a different population of spores. This process is often used when autoclaving is not feasible.

**Correct Answer:** .