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: Microbiology
Gram staining sequence is 
Select and explain. 
A. Carbol fuchsin – Iodine – Acetone – Methyl violet, B. Methyl violet  –  Iodine – Acetone – Carbol fuchsin, C. Methyl violet – Acetone – Iodine – Carbol fuchsin, D. Carbol fuchsin – Acetone – Iodine – Methyl violet
B: Methyl violet  –  Iodine – Acetone – Carbol fuchsin
Answer: B: Methyl violet  –  Iodine – Acetone – Carbol fuchsin 
Explanation: Primary stain – Crystal violet or Methyl violet 
Mordant – Gram's iodine
Decolorizer – Acetone or Ethanol
Secondary stain – Safranin or Carbol fuchsin