B
Vaccinations protect people when they are exposed to the microorganism to which they were vaccinated. This secondary response happens when the person is exposed to the microorganism. At that time, IgG production is a lot higher, making it the main antibody class in the second response. IgM is more active when it comes to the first exposure. A lot of people who have allergies have IgE in their bodies, too. IgA is the most common secretory antibody, and it stops pathogens from attaching and invading through the mucosal membranes of the body.
Jejunum if what i thought of
The answer is option a hope it helps
The answer is <span>Time is the independent variable, and the number of birds is the dependent variable. </span>
<span>An independent variable is variable that is not affected in the experiment. It is what experimenter controls. On the other side, a dependent variable is called dependent because it depends on the independent variables. It is what is affected during the experiment.
In Sam investigation, he controls time - he counts birds at 6 a.m. and 6 p.m. So, time is the independent variable. The number of birds is affected during the experiment, so it must be the dependent variable.
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