I think its the left one (sorry if im wrong)
A control variable is a scientific experiment in which the experimental element is unchanged throughout the experiment
a control group is a group in an experiment that does not receive the treatment by the researchers (untouched by them) and used to see the changes between the controlled group and that of the group that received the vial
hope this helps
Your answer here is Commensalism by process of elimination
Answer:
element Y and Z
Explanation:
Having on valence electron indicates that these elements are on the same column/group of the periodic table. Both these elements will bond with a -1 charge.
Answer:
finds the cows with a lump on his neck
