**Core Concept**
Glucose 6 phosphate is a key intermediate in glucose metabolism, and its fate is crucial in determining the body's response to glucose availability. In a well-fed state, the body's priority is to store excess glucose as energy-rich molecules for later use.

**Why the Correct Answer is Right**
In a well-fed state, the major fate of glucose 6 phosphate is to be converted to glycogen through the action of glycogen synthase enzyme. This process is facilitated by the insulin-mediated signaling pathway, which activates glycogen synthase and inhibits glycogen phosphorylase. As a result, glucose 6 phosphate is channeled into glycogen synthesis, allowing the body to store excess glucose as glycogen in the liver and muscles.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because glucose 6 phosphate is not primarily converted to lactate in a well-fed state. Lactate production is more significant in anaerobic conditions or during intense exercise.
**Option B:** This option is incorrect because glucose 6 phosphate is not primarily converted to glucose in a well-fed state. Glucose production from glucose 6 phosphate occurs mainly in fasting or starvation states.
**Option C:** This option is incorrect because glucose 6 phosphate is not primarily converted to fatty acids in a well-fed state. Fatty acid synthesis from glucose occurs mainly during periods of excessive glucose availability.

**Clinical Pearl / High-Yield Fact**
In a well-fed state, insulin promotes glycogen synthesis by activating glycogen synthase and inhibiting glycogen phosphorylase. This process allows the body to store excess glucose as glycogen, which can be broken down to glucose during fasting or starvation states.

**Correct Answer:** C. Glycogen