According to phylogenetic classification systems, organisms belonging to `:`

Options

A. Different taxa have common ancestory
B. Same taxa have different ancestory
C. Same taxa have a common ancestory
D. Different taxa have different ancestory

Answer

**Step-by-Step Solution:**

1. **Understanding Phylogenetic Classification**:
- Phylogenetic classification systems categorize organisms based on their evolutionary relationships. This means that organisms are grouped together if they share a common ancestor.

2. **Analyzing the Options**:
- The question provides four options regarding the ancestry of organisms in relation to taxa:
a. Different taxa have common ancestry.
b. Same taxa have different ancestry.
c. Same taxa have a common ancestry.
d. Different taxa have different ancestry.

3. **Evaluating Each Option**:
- **Option a**: "Different taxa have common ancestry" - This is incorrect because different taxa do not share a common ancestor in the context of phylogenetic classification.
- **Option b**: "Same taxa have different ancestry" - This is also incorrect as organisms within the same taxon are expected to share a common ancestor.
- **Option c**: "Same taxa have a common ancestry" - This is correct because organisms classified under the same taxon are derived from a common ancestor.
- **Option d**: "Different taxa have different ancestry" - This is not a valid statement in the context of phylogenetic classification since different taxa can still share a common ancestor.

4. **Conclusion**:
- The correct answer is **Option c**: "Same taxa have a common ancestry."