The correct answer is - 7.4 to 7.9 on the Mercalli scale.
The earthquake that struck Owens Valley, better known as the Lone Pine earthquake, was estimated to have a moment magnitude between 7.4 and 7.9 on the Mercalli scale, and also a maximum Mercalli intensity of X (x stands for extreme).
This part of the United States is very familiar with the earthquakes, as it is a part where there's intense geologic activity, and Lone Pine is lying above one of the many faults in the area. This earthquake contributed to the death of 27 people, and 56 more had injuries from different degrees.
