Which of the following bacterial cell surface structures may initiate B cells by T-independent antigens?ANSWERPiliFimbriaeFlagellaCapsules

Bacterial cell surface structures that may initiate B cells by T-independent antigens include:

1. Pili: These are hair-like appendages found on the surface of many bacteria. They are involved in adhesion to host cells, which can trigger an immune response.

2. Fimbriae: Similar to pili, these structures help bacteria stick to host cells and can also trigger an immune response.

3. Flagella: These are whip-like structures that allow bacteria to move. They are recognized by the immune system and can trigger an immune response.

4. Capsules: These are layers that surround the cell wall of some bacteria. They can protect the bacteria from the immune system, but can also be recognized by the immune system and trigger an immune response.

So, all of the above structures - Pili, Fimbriae, Flagella, and Capsules - can potentially initiate B cells by T-independent antigens.