**Core Concept**
Hypothyroidism in infancy, also known as cretinism, is a condition characterized by a deficiency of thyroid hormones due to congenital or early-onset thyroid dysfunction. This results in impaired growth, development, and cognitive function.

**Why the Correct Answer is Right**
In infancy, hypothyroidism can manifest with distinct clinical features, including growth failure, developmental delay, and characteristic physical abnormalities such as a large tongue (macroglossia), a wide and flat nose (depressed nasal bridge), and a prominent forehead (bossed skull). The thyroid hormone deficiency impairs the maturation of the central nervous system, leading to reduced cognitive function and IQ.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because growth failure is a characteristic feature of hypothyroidism in infancy.
**Option B:** This option is incorrect because developmental delay is a common manifestation of congenital hypothyroidism.
**Option C:** This option is incorrect because macroglossia is a well-documented physical feature of hypothyroidism in infancy.

**Clinical Pearl / High-Yield Fact**
Newborn screening programs for congenital hypothyroidism have significantly improved the early detection and treatment of this condition, reducing the incidence of intellectual disability and other long-term complications.

**Correct Answer:**
None of the options correctly lists a feature of hypothyroidism in infancy that is "except" from the choices provided.