**Core Concept**
The adolescent growth spurt in boys is a complex physiological process influenced by hormonal changes, particularly the increase in sex hormones such as testosterone. This period of rapid growth occurs during puberty and is characterized by an increase in height velocity.

**Why the Correct Answer is Right**
The growth spurt in boys is primarily driven by the surge in testosterone levels, which stimulates the production of growth hormone (GH) from the pituitary gland. GH, in turn, acts on the growth plates in the long bones, promoting an increase in the growth velocity. This process is mediated by the insulin-like growth factor-1 (IGF-1), which is produced in response to GH. The growth plates eventually close, marking the end of the growth spurt.

**Why Each Wrong Option is Incorrect**
**Option A:** The growth spurt in girls occurs earlier than in boys and is driven by the increase in estrogen levels, not testosterone.
**Option B:** The growth spurt is not primarily driven by the increase in body mass index (BMI) or caloric intake, although these factors can influence growth.
**Option C:** The growth spurt is not limited to the first year of puberty, but rather occurs over a period of several years.

**Clinical Pearl / High-Yield Fact**
The adolescent growth spurt is a critical period of development, and any disruption to this process can have long-term consequences for height and overall health. Growth hormone deficiency or other endocrine disorders can impair growth and development during this period.

**Correct Answer: C. 14-16 years.**