MADRID—Residents on the Spanish island of La Palma dared to hope Wednesday that a volcanic eruption is over after almost three months of unnerving daily explosions, earthquakes, rivers of molten rock, and a huge ash plume containing toxic gases. The Cumbre Vieja volcano in the Canary Islands off northwest Africa fell silent on Monday evening, and scientists said its 36 hours or so of negligible activity might signal the beginning of the end of the eruption. Scientists won’t rule out a resurgence of volcanic activity, which previously abated only to return with renewed force, but say it is unlikely. “We cannot be 100 percent sure, as the volcano has been playing a few tricks over the last weeks,” Valentin Troll, a geology expert with Sweden’s Uppsala University and coauthor of a geology study of the Canary Islands, told The Associated Press. “But many parameters have now subsided, and I think …