It is a completely false statement that amoebas <span>prey upon algae in aquatic environments. The correct option among all the options that are given in the question is the second option. I hope that this is the answer that you were looking for and it has actually come to your desired help.</span>
EDTA inhibits the activity of DNase during DNA isolation process.
DNase is an enzyme which degrades DNA using divalent metal ions like Mg^{2+} . These metal ions act as cofactor for the proper functioning of DNase.
EDTA chelates the divalent metal ions and thus does not allow DNase to access them.
Therefore in this way DNA is prevented from degradation during its isolation.
I think the correct answer among the choices listed above is option B. For photoperiodism to occur, a plant must use a phytochrome. This is a pigment that plants use to detect light. It is sensitive to light in the red region. Hope this answers the question.