A growth function that is O(n) is ____________________   A. constant B. logarithmic C. linear D. quadratic E. exponential

The correct answer is C. linear.

A growth function that is $O(n)$ indicates that the function grows linearly with respect to $n$. This means that as $n$ increases, the value of the function increases proportionally.

Here's a brief explanation of the other options:

• A. constant: This would be $O(1)$, meaning it does not grow with $n$.
• B. logarithmic: This would be $O(\log n)$, meaning it grows much slower than linear.
• D. quadratic: This would be $O(n^2)$, meaning it grows faster than linear.
• E. exponential: This would be $O(2^n)$ or similar, which grows very rapidly as $n$ increases.

Thus, the growth function that is $O(n)$ is best described as linear.