भू-पर्पटी के नीचे वह स्थान जहाँ भूकंपन आरम्भ होता है, कहलाता है

उत्तर: (A) उद्गम केन्द्र / Focus (Hypocenter) — The Focus (or Hypocenter) is the point below the earth's surface where an earthquake originates. The Epicenter is the point on the surface directly above the focus. Vent and Crater are related to volc...