Balanoglossus is commonly called as

Options

A. earthworm
B. tapeworm
C. lugworm
D. acorn worm

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about Balanoglossus, which is a specific organism.

2. **Common Name**: Balanoglossus is commonly known as the "corn worm." This is a key piece of information that directly answers the question.

3. **Classification**: Balanoglossus belongs to the phylum Hemichordata. This classification helps in understanding its biological context.

4. **Ecological Role**: It is noted that Balanoglossus is an ocean-dwelling organism, which provides insight into its habitat.

5. **Evolutionary Significance**: Balanoglossus serves as an evolutionary link between invertebrates and vertebrates, highlighting its importance in the study of animal evolution.

6. **Physical Characteristics**: It has a notochord in the upper part of its body, which is a significant feature in its classification. However, it does not have a nerve cord.

7. **Elimination of Incorrect Options**: The options provided (earthworm, caveworm, lumpworm) are incorrect, confirming that the correct answer is indeed "corn worm."

**Final Answer**: Balanoglossus is commonly called the "corn worm."

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