Which of the Following Statements Is Not True

Which of the following statements is not true?

A) There is no predefined upper limit to the Richter scale.
B) On worldwide average, the largest earthquakes, with Richter magnitudes over 8, occur only once every few years.
C) While great earthquakes are rare, there may be hundreds of thousands of small earthquakes each year.
D) There are many more small earthquakes than large ones and the small ones thus account for most of the seismic energy released by earthquakes each year.