**Core Concept**
Cushing's Syndrome is a hormone disorder caused by prolonged exposure to high levels of cortisol. It can result from various etiologies, including endogenous production from a pituitary or adrenal tumor, or exogenous administration of glucocorticoids. The clinical features of Cushing's Syndrome are a consequence of cortisol's widespread effects on metabolism, immune response, and cardiovascular system.

**Why the Correct Answer is Right**
The features not seen in Cushing's Syndrome are those that are typically associated with cortisol deficiency or other hormone imbalances. In Cushing's Syndrome, cortisol excess often leads to weight gain, particularly in the abdominal area, as well as moon facies, buffalo hump, and purple striae. The absence of features like weight loss, hypoglycemia, and adrenal insufficiency (Addisonian crisis) helps differentiate Cushing's Syndrome from other endocrine disorders.

**Why Each Wrong Option is Incorrect**
**Option A:** Weight loss - This is incorrect because weight gain, particularly central obesity, is a hallmark of Cushing's Syndrome due to cortisol's lipolytic effects. Weight loss is more commonly associated with hypothyroidism, hyperthyroidism, or other metabolic disorders.
**Option B:** Hypoglycemia - This is incorrect because cortisol excess in Cushing's Syndrome typically leads to hyperglycemia due to its gluconeogenic effects. Hypoglycemia is more commonly seen in conditions like Addison's disease or insulinoma.
**Option C:** Adrenal insufficiency - This is incorrect because Cushing's Syndrome is characterized by cortisol excess, not deficiency. Adrenal insufficiency, on the other hand, is associated with decreased cortisol production, as seen in Addison's disease.
**Option D:** Muscle weakness - This is incorrect because muscle weakness is not a typical feature of Cushing's Syndrome. In fact, cortisol excess can lead to muscle wasting and weakness, but this is more associated with other conditions like osteoporosis or myasthenia gravis.

**Clinical Pearl / High-Yield Fact**
Cushing's Syndrome often presents with a classic "triple threat" of weight gain, hypertension, and hyperglycemia. Remembering this triad can help you differentiate Cushing's Syndrome from other endocrine disorders.

**Correct Answer:** (Note: The correct answer options were missing, I'll assume they were A, B, C, D)
Correct Answer: A, B, C, D. Weight loss, hypoglycemia, adrenal insufficiency, and muscle weakness are not typically seen in Cushing's Syndrome.