One of the following can cause thrombocytopenia with decreased megakaryocytes in bone marrow:

Correct Answer: B

Rationale: Aplastic anemia results from bone marrow failure, leading to pancytopenia, including decreased megakaryocytes, which causes thrombocytopenia. Other causes, such as ITP and hypersplenism, typically have normal or increased megakaryocytes.

Correct Answer: D

Rationale: Self-biting is not typically classified as a stereotypic movement but rather as a self-injurious behavior.

Correct Answer: C

Rationale: Wilson's disease is an autosomal recessive disorder with defective copper excretion, leading to low ceruloplasmin and copper accumulation.

Correct Answer: A

Rationale: Folic acid deficiency leads to megaloblastic anemia with macrocytosis, unlike conditions such as sickle cell disease and beta thalassemia, which cause microcytosis.

Correct Answer: B

Rationale: Hyperinsulinism is a common cause of persistent neonatal hypoglycemia due to excessive insulin production. It requires medical management with dextrose infusions or medications like diazoxide to prevent neurodevelopmental impairment.