Which of the following is measured on the Richter scale?

Option B

The Richter scale– also called the Richter magnitude scale or Richter's magnitude scale – is a measure of the strength of earthquakes, developed by Charles F. Richter and presented in his landmark 1935 paper, where he called it the "magnitude scale". This was later revised and renamed the local magnitude scale, denoted as ML or M_L . Because of various shortcomings of the M_L  scale most seismological authorities now use other scales, such as the moment magnitude scale (M_w ), to report earthquake magnitudes, but much of the news media still refers to these as "Richter" magnitudes. All magnitude scales retain the logarithmic character of the original and are scaled to have roughly comparable numeric values (typically in the middle of the scale).