Digestive enzymes are
(a) hydrolases
(b) oxidoreductases
(c) transferases
(d) lyases

Options

A. hydrolases
B. oxidoreductases
C. transferases
D. lyases

Explanation

### Step-by-Step Solution:

1. **Understanding Digestive Enzymes**: Digestive enzymes are biological catalysts that help in breaking down food substances into smaller, absorbable units. They act on macromolecules such as carbohydrates, proteins, and fats.

2. **Types of Enzymatic Reactions**: Enzymes can be classified based on the type of reaction they catalyze. The options given are:
- (a) Hydrolases
- (b) Oxidoreductases
- (c) Transferases
- (d) Lyases

3. **Identifying the Correct Type**:
- **Hydrolases**: These enzymes catalyze hydrolysis reactions, where water is used to break chemical bonds. This is the primary action of digestive enzymes as they break down complex molecules into simpler ones.
- **Oxidoreductases**: These enzymes are involved in oxidation-reduction reactions, which are not primarily the action of digestive enzymes.
- **Transferases**: These enzymes transfer functional groups from one molecule to another, which is not the main function of digestive enzymes.
- **Lyases**: These enzymes catalyze the addition or removal of groups to form double bonds, which is also not the main function of digestive enzymes.

4. **Conclusion**: Since digestive enzymes primarily function through hydrolysis, the correct answer is (a) Hydrolases.

### Final Answer:
Digestive enzymes are (a) hydrolases.

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