One of these is not a feature of nonchordates

Options

A. Absence of postanal tail
B. Ventrally located central nervous system
C. Absence of notochord
D. Ventrally of located heart

Answer

To determine which of the given options is not a feature of nonchordates, we can analyze each option step by step.

### Step-by-Step Solution:

1. **Understanding Nonchordates**: Nonchordates are a diverse group of animals that do not possess a notochord, which is a defining characteristic of chordates. They include various phyla such as arthropods, mollusks, and annelids.

2. **Analyzing the Options**:
- **Option 1: Absence of the post-anal tail**: This is a correct feature of nonchordates. Nonchordates typically do not have a post-anal tail, which is a characteristic feature of chordates.

- **Option 2: Ventral location of the central nervous system**: This is also a correct feature of nonchordates. In nonchordates, the central nervous system is usually ventrally located, meaning it is situated on the belly side of the organism.

- **Option 3: Absence of notochord**: This is true for nonchordates. They do not possess a notochord, which is a defining feature of chordates.

- **Option 4: Ventral location of the heart**: This option is incorrect for nonchordates. While some nonchordates may have a heart, it is typically located dorsally (on the back side) rather than ventrally (on the belly side). The ventral heart is a characteristic of some chordates.

3. **Conclusion**: The option that is not a feature of nonchordates is the "ventrally located heart." This is the correct answer to the question.

### Final Answer:
The option that is not a feature of nonchordates is the "ventrally located heart."