What causes the condition known as dwarfism?

Dwarfism is primarily caused by a deficiency in growth hormone, which is crucial for normal growth and development during childhood. Growth hormone plays a vital role in stimulating growth in bones and tissues. When the body doesn't produce enough of this hormone, it can lead to reduced growth and stature, resulting in dwarfism.

While dwarfism can be influenced by other factors such as genetic mutations associated with various syndromes, the most direct and well-known cause linked to a lack of growth is indeed the deficiency of growth hormone. This type of dwarfism is often referred to as growth hormone deficiency dwarfism and is characterized by shorter stature compared to peers, along with other potential health concerns related to growth and development.

The other options provided, such as deficient calcium or excess growth hormone, do not align with the primary understanding of dwarfism causes. Genetic mutations can contribute to specific types of dwarfism, but the key factor that leads to the common form of dwarfism is the lack of growth hormone.