Which of the following show embryonic development by the deuterostome pathway ?

Options

A. Annelids
B. Chordates
C. Molluscs
D. Arthropods

Explanation

To determine which organisms show embryonic development by the deuterostome pathway, follow these steps:

### Step-by-Step Solution:

1. **Understand Deuterostome Development**:
- Deuterostomes are a group of animals characterized by their embryonic development. In deuterostomes, the first opening that forms during embryonic development becomes the anus, while the mouth forms secondarily.

2. **Identify the Major Groups of Deuterostomes**:
- The two main groups of deuterostomes are:
- **Echinoderms**: This group includes marine animals such as sea stars (starfish) and sea urchins.
- **Chordates (or Caudates)**: This group includes all vertebrates, such as humans, horses, and other animals with a backbone.

3. **Analyze the Options**:
- Look at the options provided in the question (not specified here). If the options include organisms from the echinoderm or chordate groups, they would be classified as deuterostomes.

4. **Select the Correct Group**:
- Since the question does not specify any echinoderms, focus on the chordates. All vertebrates, including humans and horses, are deuterostomes.

5. **Conclusion**:
- The correct answer to the question is that organisms from the **Chordates (Caudates)** show embryonic development by the deuterostome pathway.