Answer:
C) period
Explanation:
Groups are columns on the periodic table (with the same number of electrons on the outer shell of the elements), whereas periods are rows (increasing in atomic number by 1 - 5, 6, 7, 8, 9 etc.)
Yes, there is growing evidence that cognitive impairment is associated with cigarette smoking.
The first level of organization are living cells
I think it is B, that helps disprove it so it can't prove it.
