Function of Saliva in Digestion
Saliva plays a crucial role in the digestive process, particularly in the breakdown of starches.

Composition of Saliva
- Saliva is composed mainly of water, electrolytes, mucus, and enzymes.
- The most significant enzyme present in saliva is **amylase** (specifically salivary amylase or ptyalin).

Role of Salivary Amylase
- **Starch Breakdown**: Salivary amylase initiates the process of starch digestion by breaking down complex carbohydrates (starches) into simpler sugars like maltose and dextrin.
- **Chemical Reaction**: When food is chewed and mixed with saliva, amylase begins to hydrolyze starch molecules, making them more accessible for further digestion in the stomach and small intestine.

Facilitation of Taste and Swallowing
- **Taste Enhancement**: Saliva helps dissolve food particles, allowing taste buds on the tongue to detect flavors more effectively.
- **Lubrication**: It moistens food, facilitating easier swallowing and preventing irritation in the esophagus.

Overall Importance
- Saliva not only aids in the mechanical breakdown of food but also begins the chemical digestion of starches.
- This enzymatic action is vital for the efficient absorption of nutrients later in the digestive tract.
In summary, while saliva has multiple functions, its primary role in digestion revolves around the enzymatic breakdown of starches, making option 'A' the correct answer.