It will be Control. Part of the experiment used to show that the results of an experiment is really due to the conditions being tested.
Answer : A metal in group 16 of the periodic table can become a chemically stable ion by gaining 2 electrons.
Explanation :
The group 16 element are oxygen, sulfur, selenium, tellurium and polonium.
The general electronic configuration of group 16 elements is, 
As we now that there are total 6 electrons in p sub-shell. So, a metal in group 16 can become a chemically stable ion by gaining 2 electrons.

Hence, a metal in group 16 of the periodic table can become a chemically stable ion by gaining 2 electrons.
Answer:
Choloroplast
Explanation:
The choloroplast hosts the enzymatic machinery that carries out photosynthesis. These proteins are embedded in the thylakoid membranes of the chloroplast. Of these proteins PSII and PSI contain chlorophyll molecules.