Question

which of the following act as a second line of defense in our innate immune response? b cells t cells white blood cells

Explanation:

Innate immune response has first (physical/chemical barriers) and second lines. B and T cells are part of adaptive (not innate) immunity. White blood cells (like phagocytes, natural killer cells) are part of innate immunity's second line, acting to defend against pathogens that breach first line.

Answer:

white blood cells