A. A concentration of total ions dissolved in solution
B. A measurement indicating how acidic a solution is
C. A component of solutions that makes them acidic
D. A level of dissolved gases that are in solution
B is your answer because anything lower than 7 is acidic, anything above 7 is considered to be a base. Anything in the 7 range is considered to be neutral. Your colors will change too. Acid - red, base - blue, neutral - purple. Have a great day!
