The Magnitude M of an Earthquake Depends on the Relative $M = \log I$

Multiple Choice

The magnitude M of an earthquake depends on the relative intensity I of the quake. The relationship is $M = \log I$
Express the relative intensity as a function of the magnitude.

A) $I = 10 ^ { M }$
B) $I = e ^ { M }$
C) $I = \log M$
D) $I = \ln M$