Answer:
<h2>C. As more pure acid is added, the concentration of acid approaches 0.</h2>
Step-by-step explanation:
The given function is

The graph of this function is attached. There you could see that the horizontal asymptote is the x-axis.
You can observe that the greater amount of acid, the more concentration.
Therefore, the answer that best fits the asymptote interpretation is
<em>C. As more pure acid is added, the concentration of acid approaches 0.</em>
<em />
Because, you can see that the greater x-variable is, y-variable approaches more to zero.