Which Statement About Regulatory T Cells (Tregs) Is True

Which statement about regulatory T cells (Tregs) is true?

A) Tregs are similar to T-helper cells and cytotoxic T cells in that they are produced in the thyroid gland.
B) Tregs differ from T-helper cells and cytotoxic T cells in that they are activated when they bind antibodies.
C) Tregs suppress the cellular immune response against self antigens.
D) Destruction of Tregs would severely reduce the recognition of non-self antigens.
E) Activated Tregs secrete perforin, which stimulates proliferation of B cells.