Question 3(Multiple Choice Worth 5 points) (07.06 MC)
Which of the following best describes an example of a specific internal response to harmful bacteria?
Skin serves as a physical barrier that prevents bacteria from entering the body.
Saliva contains enzymes that destroy bacteria and prevent infection.
Bacterial infection causes the release of histamine, which leads to inflammation and swelling.
Antigens trigger the production of antibodies, which mark bacteria for destruction.

A the skin is the bodies first line of defense

Explanation:

The first line of defence is non-specific and aims to stop microbes from entering the body. 

Antigens trigger the production of antibodies, which mark bacteria for destruction.

Explanation:

The question is talking about internal response to bacteria so we have to look at what happens inside the body pertaining to bacterial infection, so the answer is "Antigens trigger the production of antibodies, which mark bacteria for destruction".

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.

the answer would be d : p