The correct answer is option 2: Both the statements are individually true but Statement II is NOT the correct explanation of Statement I.

Statement I is true as the Indian Ocean Tsunami of 2004 did occur along a subduction zone along the west coast of Sumatra. Subduction zones occur when one tectonic plate moves beneath another, and in this case, the Indo-Australian Plate is converging below the Eurasian Plate.

However, Statement II is not the correct explanation of Statement I. While it is true that along the Sumatra coast the Indo-Australian Plate converges below the Eurasian Plate, this convergence is not the direct cause of the tsunami. The Indian Ocean Tsunami of 2004 was primarily triggered by a massive undersea earthquake with a magnitude of 9.1–9.3, which occurred off the west coast of northern Sumatra. This earthquake caused the seafloor to uplift, displacing a large volume of water and creating the tsunami.

Therefore, while both statements are true, Statement II does not explain the occurrence of the Indian Ocean Tsunami of 2004. The tsunami was primarily caused by the undersea earthquake, rather than the convergence of tectonic plates along the Sumatra coast.