**Core Concept**
Capacitation is a physiological change that spermatozoa undergo in the female reproductive tract, specifically in the fallopian tube, which enables them to fertilize an egg. It involves a series of biochemical changes that modify the sperm membrane, allowing it to bind to the egg's zona pellucida and facilitate fertilization.

**Why the Correct Answer is Right**
Capacitation involves the activation of certain enzymes, such as phospholipase C, which hydrolyzes phospholipids in the sperm membrane, creating a receptive environment for the egg. The process also involves changes in the sperm's calcium and sodium ion concentration, as well as the expression of specific proteins on the sperm surface. These changes enable the sperm to undergo the acrosome reaction, which is essential for fertilization.

**Why Each Wrong Option is Incorrect**
**Option A:** This statement could be true, as capacitation does indeed involve changes in the sperm's membrane potential and ion flux. However, the specific details of this process are not as well-defined as those of other aspects of capacitation.
**Option B:** This statement is true, as capacitation does involve changes in the sperm's protein expression and binding properties. However, it is not the most accurate or comprehensive description of capacitation.
**Option C:** This statement is false, as capacitation does not involve the activation of the sperm's flagellum. In fact, the flagellum is not directly involved in the capacitation process.

**Clinical Pearl / High-Yield Fact**
It's worth noting that capacitation is a critical step in fertilization, and any disruptions to this process can lead to infertility. Additionally, capacitation is a highly regulated process that can be influenced by various factors, including the presence of certain proteins or chemicals in the female reproductive tract.

**Correct Answer: C. Capacitation does not involve the activation of the sperm's flagellum.**