This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Biochemistry
In which organelle (s) of hepatocyte, the elongation of long chain fatty acid takes placea) Endoplasmic reticulum (ER)b)  Golgi bodyc) Mitochondriad) Lysosomese) Ribosome 
Select and explain. 
A. ac, B. bc, C. ad, D. b
A: ac
Answer: A: ac 
Explanation: Endoplasmic reticulum (E ) & i.e., Mitochondria

Elongation takes place in microsomal system (endoplasmic reticulum) and mitochondrial system.