Jeff is investigating factors that affect the growth rate of potted bean plants. Which of the following experimental variables would not be relevant to his investigation? A.
the amount of light exposure
B.
the amount of water given
C.
the color of the pot
D.
the type of soil used

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link:

chert is a sedimentary rock composed of microcrystalline or cryptocrystalline silica. with this little bit of information, you can come to the conclusion that your answer is c.  

explanation: