A................ is a systematic enumeration of plant species occurring in a given region.

Explanation

**Step-by-Step Solution:**

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

2. **Identify Key Terms**: The key terms in the question are "systematic enumeration," "plant species," and "given region." This indicates that we are looking for a classification or listing of plants.

3. **Recall Relevant Concepts**: In biology, the term "flora" is commonly used to describe the plant life occurring in a particular region. It encompasses all the plant species found in that area.

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