Explanation:

Major earthquake events in last 30,000 years resulted in spectacular changes in landscape of the Katrol Hill Fault in the Kachchh region in Gujarat, a study conducted on sediment samples revealed.

• Seismicity in Kachchh region is highly complex as it is characterized by multiple seismic sources in the form of several East-West trending fault lines, which release continuously accumulating tectonic stresses at intervals producing earthquakes.
• Real-time monitoring of earthquakes since the occurrence of devastating 2001 Bhuj earthquake indicate that most of the faults in the region, viz., Kachchh Mainland Fault (KMF), South Wagad Fault (SWF), Gedi Fault (GF), and Island Belt Fault (IBF) are seismically active.
• However, seismic activity along other faults like the Katrol Hill Fault (KHF) is not apparent, thus making the task of seismic hazard estimation and mitigation in the region a scientifically complex process.

Hence option 1st is correct.