Spleen develops from

Options

A. Ectoderm
B. Mesoderm
C. Endoderm
D. None of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding the Spleen's Function**: The spleen is often referred to as the "graveyard of RBCs" because it plays a crucial role in the destruction and recycling of red blood cells (RBCs).

2. **Identifying Germ Layers**: In embryonic development, there are three primary germ layers: ectoderm, mesoderm, and endoderm. Each of these layers gives rise to different tissues and organs in the body.

3. **Determining the Origin of the Spleen**: The spleen develops from the mesoderm. Specifically, it arises from the aggregation of mesenchymal cells, which are derived from the mesodermal layer.

4. **Conclusion**: Based on the information about germ layers and the development of the spleen, the correct answer to the question "Spleen develops from" is the mesoderm.

**Final Answer**: The spleen develops from the mesoderm.

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