In which of the following pair of category, greater is the difficulty of determining the relationship to other taxa at the same level, thus the problem of classification becomes more complex?

Options

A. Genus and species
B. Tribe and genus
C. Division and phylum
D. Species and family

Answer

To solve the question regarding the difficulty of determining relationships among taxa at the same level, we need to analyze the pairs of categories provided:

1. **Genus and Species**: These are closely related categories, with species being a subset of genus. The relationship is relatively easy to determine because species within a genus share many characteristics.

2. **Tribe and Genus**: Tribe is a higher taxonomic rank than genus. While there may be some complexity, the relationship is still manageable as genera within a tribe share common features.

3. **Division and Phylum**: Division and phylum are often used interchangeably in different contexts (especially in botany and zoology). They represent high taxonomic ranks, and the relationship can be complex due to the broader range of organisms included.

4. **Species and Phylum**: This pair shows a significant difference in taxonomic rank, with species being a very specific classification and phylum being much broader. The relationship is complex because species within a phylum can be vastly different from one another.

Based on this analysis, the pair that presents the greatest difficulty in determining relationships at the same level is **Species and Phylum**. This is due to the vast differences in the scope and characteristics of the organisms classified under these two categories.

**Final Answer**: The pair with the greatest difficulty in determining relationships at the same level is **Species and Phylum**.

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