I asked this a few minutes ago and i forgot to add the other picture! but please help

like said "will give brainliest!!!"

What is an important step to prove something is valid or not? determining the reliability observing research testing

True or false mucous membranes destroy pathogens on the outer body surface, at body openings.

Which of the following is an important part of good posture? a. slumped shoulders b. arched back c. feet shoulder-width apart d. belly out