Which of the following is chiefly seen in infants and children?

The correct answer, neuroblastoma, is indeed chiefly seen in infants and children and is the most common type of cancer found in this specific age group, particularly in those under five years old. Neuroblastoma originates from immature nerve cells found in several areas of the body, including the adrenal glands, sympathetic nervous system, and spinal cord. Its high incidence among infants and young children makes it a significant pediatric cancer.

Neuroblastoma often presents with various symptoms, including abdominal swelling or a noticeable lump, depending on its location. The disease can also affect other areas, leading to bone pain or symptoms related to the nervous system. Early detection and diagnosis are crucial in managing the condition, which can sometimes spontaneously regress in very young children.

While the other options listed are also associated with pediatric cancers, they do not have the same prevalence as neuroblastoma in infancy and early childhood. Retinoblastoma primarily affects very young children but is less common than neuroblastoma. Leukemia does occur in children but encompasses a wide range of ages and doesn't specifically peak in infancy. Rhabdomyosarcoma, although a soft tissue sarcoma that can occur in children, is not as prevalent as neuroblastoma in the same age group.