30 ! which is not one of the body's natural barriers against pathogens? a. stomach acid b. freckles

The correct answer is option "B"

Explanation:

Natural barriers include the skin, mucous membranes, tears, earwax, mucus, and stomach acid. Also, the normal flow of urine washes out microorganisms that enter the urinary tract.

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.