Final answer:
An overabundance of human growth hormone can lead to gigantism in children and acromegaly in adults, resulting in excessive tissue growth and bone enlargement. The correct option is d).
Step-by-step explanation:
An overabundance of human growth hormone (GH) can cause excessive growth of body tissues. In children, this can lead to gigantism, characterized by heights that may exceed eight feet. For adults, an overproduction of growth hormone could result in acromegaly, where there's an enlargement of bones in the face, hands, and feet.
\Acromegaly is a condition directly associated with the overproduction of GH in adults and is known for causing changes in physical appearance such as a protruding jaw, enlarged hands and feet, and potentially leading to other health complications. Option d) is the correct one.