**Core Concept**
The hypothalamic temperature controller regulates body temperature by adjusting heat loss and heat production. The set point is the optimal temperature maintained by the body, and changes in this set point can affect thermoregulation.

**Why the Correct Answer is Right**
When the set point is decreased (point W), the body tries to conserve heat by reducing heat loss and increasing heat production. This is achieved by vasoconstriction (decreased blood flow to the skin), shivering, and increasing metabolic rate. In contrast, at point V (higher set point), the body tries to dissipate heat by increasing heat loss and reducing heat production. This is achieved by vasodilation (increased blood flow to the skin), decreased metabolic rate, and sweating.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe the changes that occur at point W compared to point V. At point W, the body is trying to conserve heat, not increase heat loss.
**Option B:** This option is incorrect because it does not accurately describe the changes that occur at point W compared to point V. At point W, the body is trying to conserve heat, not increase metabolic rate.
**Option C:** This option is incorrect because it does not accurately describe the changes that occur at point W compared to point V. At point W, the body is trying to conserve heat, not increase heat loss through sweating.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that the hypothalamic temperature controller is a temperature-regulating mechanism that maintains homeostasis. When the set point is altered, the body responds by adjusting heat loss and heat production to maintain the new temperature.

**Correct Answer: C. Increased vasoconstriction, shivering, and decreased heat loss.**