Systematic enumeration of plant species occurring in a given region is called :
(a) flora
(b) fauna
(c) monograph
(d) manual

Options

A. flora
B. fauna
C. monograph
D. manual

Explanation

To solve the question regarding the systematic enumeration of plant species occurring in a given region, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: The question asks for the term that describes the systematic enumeration of plant species in a specific region.

2. **Define the Options**:
- **Option (a) Flora**: This term refers to all the plant species that naturally occur in a particular region.
- **Option (b) Fauna**: This term refers to all the animal species that naturally occur in a particular region.
- **Option (c) Monograph**: This term refers to a detailed written study or account of a single taxon (group of organisms).
- **Option (d) Manual**: This term refers to a handbook or guide that provides instructions or protocols.

3. **Analyze the Definitions**:
- Since the question specifically mentions "plant species," we can eliminate options (b), (c), and (d) as they do not pertain to plants.
- **Flora** is specifically related to plants and encompasses all the plant species found in a certain area.

4. **Select the Correct Answer**: Based on the definitions and the context of the question, the correct answer is **(a) Flora**.

### Final Answer:
The systematic enumeration of plant species occurring in a given region is called **(a) flora**.

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