Earthquake refers to the vibration on the earth's surface caused by catastrophic endogenetic forces.

(A) The magnitude or intensity of energy released by an earthquake is not measured by the modified Mercalli Intensity Scale.
(B) The place on the ground surface which is perpendicular to the focus is called the epicenter.
(C) Seismology is the special branch of geology that deals with the study of earthquakes.
(D) Shadow zones are some specific areas where earthquake waves do not occur or occur rarely.

Choose the correct answer from the options given below:

(B), (C) and (D) only

The correct answer is Option (4) → (B), (C) and (D) only

• (A): Incorrect. The Modified Mercalli Intensity Scale measures the intensity (observed effects and shaking) of an earthquake, not the magnitude (total energy released). Magnitude is measured by scales like Richter or Moment Magnitude.
• (B): Correct. The epicenter is the point on the Earth's surface directly above (perpendicular to) the focus (hypocenter), where the earthquake originates.
• (C): Correct. Seismology is the scientific branch (of geophysics/geology) that studies earthquakes and seismic waves.
• (D): Correct. Shadow zones are specific areas on Earth's surface where certain seismic waves (P or S) are absent or weakened due to refraction/reflection in Earth's interior (e.g., P-wave shadow zone 103°–142° from epicenter; S-waves blocked beyond 103° by liquid outer core).

Thus, only (B), (C), and (D) are accurate statements.