Consider a free lysine amino acid in a solution buffered to pH = 9.00. What will be the overall charge on the residue? Is it -2, -1, 0, 1, 2?

Option A

Explanation:

Remember constant means staying the same so in order to remain constant on the graph the line has to keep going up remaining the same pace. Which means the answer is option A or "Object A." The graph consists of a line going up at a constant speed without any bends or turns which all the other options consist of.

Hope this helps.