Since 2014, there have been more than 230 earthquakes of magnitude 3 and above in a certain state, and this number was an average of 1 before 2008. Frequent seismic activity has raised questions. Some researchers have discovered that since 2014, in order to avoid the pollution of surface water from toxic wastewater generated during drilling and hydraulic fracturing in oil mining, the wastewater has been injected into the impervious water of underground rocks Between layers, this behavior is likely to be the key reason for the earthquake. Which of the following, if true, best supports the above speculation? ['Wastewater pouring into the rocky water layer will reduce the friction between faults and make it easier to slide, thus inducing an earthquake.', 'The state has explored more oil reserves since 2008, and oil extraction activities have increased significantly.', 'The state had fewer earthquakes before 2008 but larger magnitudes, and more earthquakes since 2014 but smaller magnitudes.', 'Most continuous earthquakes are a series of aftershocks that occur after a strong earthquake, but the earthquake in this state is not the case.']