**Core Concept**
The Positive G effect refers to the physiological response to intense acceleration forces, particularly in the context of high-G environments such as fighter pilots or space travel. This phenomenon is characterized by a reduction in blood flow to the brain, leading to symptoms like grayout, blackout, and ultimately, G-LOC (G-induced Loss of Consciousness).

**Why the Correct Answer is Right**
During intense acceleration, the force of gravity pushes blood downwards, away from the brain. The body's attempt to counteract this effect involves the activation of the baroreceptors in the carotid sinus and aortic arch, which detect the decrease in blood pressure. This triggers a reflexive increase in sympathetic activity, causing vasoconstriction in the peripheral vasculature and a decrease in cardiac output. The resulting reduction in blood flow to the brain is what contributes to the Positive G effect.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not address the physiological response to intense acceleration forces.
**Option B:** This option is incorrect because it does not relate to the specific context of the Positive G effect.
**Option C:** This option is incorrect because it is not a recognized consequence of the Positive G effect.

**Clinical Pearl / High-Yield Fact**
The Positive G effect is a critical concern in high-G environments, and understanding its mechanisms is essential for the development of countermeasures to prevent G-LOC and other related complications.

**Correct Answer: C. G-LOC (G-induced Loss of Consciousness)**