This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Toxicology - 2, Subject name: Forensic Medicine
A small girl with neuropsychiatry symptoms has a habit of licking paint in walls .Symptoms due to inhibition of 
Select and explain. 
A. ALA dehydratase, B. ALA synthase, C. Heme oxygenase, D. CPG oxidase
A: ALA dehydratase
Answer: A: ALA dehydratase 
Explanation: It is a case of lead poisoning. Specifically, lead decreases heme biosynthesis by inhibiting aminolevulinic acid dehydratase (ALAD) and ferrochelatase. patients presents with microcystic hypochromic anemia.