Which group of animals has stomochord?

Explanation

**Step-by-Step Solution:**

1. **Understanding Stomochord**: The first step is to define what a stomochord is. A stomochord is a flexible, hollow tube-like structure that is involved in embryonic development. It extends from the root of the embryonic gut to the pharynx.

2. **Identifying the Group of Animals**: Next, we need to identify which group of animals possesses this structure. The stomochord is a unique feature found in the phylum Hemichordata.

3. **Characteristics of Hemichordata**: Hemichordates are organisms that exhibit characteristics that are partly similar to chordates and partly similar to echinoderms. They are considered a transitional group between these two phyla.

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