**Core Concept**
The question is related to the properties of dental amalgam, a material used for filling teeth. The strength of dental amalgam is crucial for its durability and longevity. The process of hardening mercury/silver alloy involves several phases, each contributing to the final properties of the amalgam.

**Why the Correct Answer is Right**
The correct answer is related to the **phase transformation** that occurs during the hardening process. When mercury reacts with silver, it forms a crystalline structure that provides strength to the amalgam. This reaction involves the formation of **gamma-2 (γ2) phase**, which is responsible for the maximum strength in hardened mercury/silver alloy. The γ2 phase is a complex compound of silver and tin that forms when the amalgam is aged or when it undergoes a process called **spheroidization**.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not relevant to the hardening process of mercury/silver alloy. It is possible that this option might be related to a different property or phase, but it is not the correct answer in this context.
* **Option B:** This option might be related to a different phase or property of the amalgam, but it is not the correct answer. The **alpha (α) phase** is present in the early stages of the hardening process, but it is not responsible for the maximum strength.
* **Option C:** This option might be related to a different type of dental material or a different process, but it is not the correct answer in this context.

**Clinical Pearl / High-Yield Fact**
The γ2 phase is responsible for the maximum strength in hardened mercury/silver alloy, which is essential for the longevity and durability of dental amalgam fillings. It is crucial for dentists to understand the properties of dental materials to provide effective treatment.

**Correct Answer:** C.