Which of the following are the natural barriers that keep infection out?
question 2 options:

a)

tears and skin

b)

masks

c)

mucous membranes and skin

d)

both a and c

how do pathogens spread?
question 3 options:

a)

indirect contact

b)

direct contact

c)

animal or insect

d)

contaminated food or water

e)

all of the above