What is the comparison of the formula for the period of a pendulum to the equation of a line?

What is the comparison of the formula for the period of a pendulum to the equation of a line? The formula for the period of a pendulum: $2 \pi \sqrt{\frac{l}{g}}$ The formula for the equation of a line: $y = m x + c$

The period of the pendulum varies less fast than a straight line, except when $\frac{l}{g} < 1$
The period of a pendulum varies like the square root of its length. The square root is always below the straight line, except for $\frac{l}{g} < 1$ in which case $\sqrt{\frac{l}{g}} > \frac{l}{g}$.