The question asks which of the provided options is a lymphoid organ. Let's evaluate each one:
- Tonsil: The tonsils are part of the lymphatic system. They help protect the body against respiratory and gastrointestinal infections.
- Spleen: The spleen is a major lymphoid organ that filters blood, recycles iron, and produces lymphocytes, which are white blood cells involved in immune responses.
- Thymus: This organ is crucial for the development of T-cells, a type of lymphocyte. It is considered a primary lymphoid organ.
Since all three—tonsil, spleen, and thymus—are lymphoid organs, the correct answer is:
All of these