**Core Concept**
Infantile tremor syndrome is a condition characterized by a unique combination of symptoms, including tremors, weight loss, and developmental delay, typically presenting in infants between 6-36 months of age. It is believed to be caused by a specific nutritional deficiency and is often associated with a history of malnutrition or inadequate diet. The exact pathophysiology is not fully understood, but it is thought to involve a deficiency in certain essential nutrients.

**Why the Correct Answer is Right**
Infantile tremor syndrome is often linked to a deficiency in vitamin B6 (pyridoxine) and other essential nutrients, which are crucial for brain development and function. The tremors and developmental delay seen in this condition are thought to result from impaired neurotransmitter synthesis and neuronal function. Research suggests that a deficiency in pyridoxine can lead to impaired activity of enzymes involved in neurotransmitter metabolism, including gamma-aminobutyric acid (GABA) synthesis.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not accurately describe the primary cause of infantile tremor syndrome.
**Option B:** This option is incorrect as it mentions a different condition altogether, which is not related to infantile tremor syndrome.
**Option C:** This option is incorrect as it does not specify the correct nutritional deficiency associated with infantile tremor syndrome.

**Clinical Pearl / High-Yield Fact**
Infantile tremor syndrome is a classic example of a condition caused by a nutritional deficiency, highlighting the importance of a balanced diet for optimal brain development and function. This condition should be considered in the differential diagnosis of infants presenting with tremors and developmental delay.

**Correct Answer: D.**