<span>A method of procedure that has characterized natural science since the 17th century, consisting in systematic observation, measurement, and experiment, and the formulation, testing, and modification of hypotheses.</span>
Since a secondary source is a source written after an event has occurred, I want to say that the answer is A. Hope this helped!<span />
I am pretty sure that would be <span>wrist flexors</span>
amylase breaks down starch sweet potatoes have a lot of starch
