There are 118 elements in the periodic table.
Answer: Vinegar
Explanation:
The vinegar and salt affects the shell because food coloring does not affect anything besides the color so the viniger has substances which dissolves thing and the salt just made the vinegar a stronger substance. The Vinegar reactes to form a compund on the shell.
Its would be fluorine as its the most electronegative
hope that helps <span />
Your answer would be A for your homework