18. A molecule such as 2,4-dinitrophenol (2,4-DNP) works to uncouple the proton gradient. Which of the followingis true about 2,4-DNP?
(A) 2,4-DNP is protonated in the matrix and deprotonated in the intermembrane space.
(B) The presence of an uncoupler results in an increase in the activity of the TCA cycle and electron transport.
(C) 2,4-DNP is a very ineffective uncoupler because its hydrophobic structure prevents it from effectivelycrossing lipid bilayer membranes.
(D) 2,4-DNP has been used as a very effective diet aid for the past 70 years.
(E) None of the above is correct.