Which of the following 'suffixes' used for units of classification in plants indicates a taxonomic category of 'family' ?

Options

A. `-`Ales
B. `-`Onae
C. `-`Aceae
D. `-`Ae

Explanation

To determine which suffix indicates a taxonomic category of 'family' in plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Taxonomic Hierarchy**: Familiarize yourself with the levels of classification in biology, which include domain, kingdom, phylum, class, order, family, genus, and species.

2. **Identify Suffixes in Taxonomy**: Recognize that suffixes are letters or groups of letters added at the end of a word to indicate a specific meaning or category. In the context of plant classification, different suffixes are used for different taxonomic ranks.

3. **Focus on the Family Category**: Specifically, we need to find the suffix that corresponds to the family category in plant taxonomy.

4. **Recall Common Suffixes**: The common suffixes used in plant taxonomy include:
- **-aceae**: This is the suffix used for the family category.
- Other suffixes like -ales (for orders) and -inae (for subfamilies) are also important but not relevant to this question.

5. **Provide Examples**: Examples of plant families that use the suffix -aceae include:
- **Solanaceae** (the nightshade family)
- **Leguminaceae** (the legume family)

6. **Conclude the Answer**: Based on the above steps, the suffix that indicates a taxonomic category of 'family' in plants is **-aceae**.

### Final Answer:
The suffix used for units of classification in plants that indicates a taxonomic category of 'family' is **-aceae**.

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