✅ Correct Answer: 2) Serosa → Muscularis → Submucosa → Mucosa

🔍 Explanation:

The alimentary canal (digestive tract) wall is made up of four layers, arranged from outside to inside as follows:

1. Serosa – The outermost layer; a thin protective membrane (also called the visceral peritoneum).
2. Muscularis – Made of smooth muscles; responsible for peristalsis (movement of food).
3. Submucosa – A layer of connective tissue with blood vessels, nerves, and glands.
4. Mucosa – The innermost layer; it secretes mucus, digestive enzymes, and absorbs nutrients.

So the correct outer to inner sequence is:
Serosa → Muscularis → Submucosa → Mucosa