Which of the following is a characteristic feature of 1p36 deletion syndrome?

1p36 deletion syndrome is characterized by a variety of symptoms, making the presence of multiple features quite common. Facial dysmorphism is a hallmark of this condition, with individuals often displaying specific facial characteristics such as a prominent forehead, deep-set eyes, and a narrow face. Hypotonia, or decreased muscle tone, is also significantly associated with the syndrome, which can affect an individual's motor development and ability to perform daily activities. Additionally, individuals with 1p36 deletion syndrome are at risk for a shortened life expectancy due to associated health complications and developmental challenges.

Given that all these features—facial dysmorphism, hypotonia, and shortened life expectancy—are associated with 1p36 deletion syndrome, the correct answer encompasses the full spectrum of characteristics observed in affected individuals. Each of these aspects contributes to the clinical presentation of the syndrome and highlights the multifaceted nature of its impact on health and development.