Step 1: Understanding the Concept:
Different classes of nutrients, carbohydrates, fats, proteins and vitamins, are broken down by different, specific enzymes in the digestive tract, and the question wants the nutrient class matched to salivary amylase.
Step 2: Key Concept or Approach:
Match each nutrient in the options to the enzyme that actually digests it, then see which one lines up with amylase.
Step 3: Detailed Explanation:
Fats are broken down by lipases, not amylase.
Vitamins pass through digestion largely unchanged and need no enzyme to break them apart.
Proteins are digested by pepsin and later by trypsin and chymotrypsin.
Starch, a polysaccharide, is the substrate that salivary amylase (ptyalin) breaks down into maltose and smaller dextrins, right from the moment food is chewed and mixed with saliva.
Step 4: Final Answer:
Salivary amylase helps digest starch.