Final answer:
The type of lava flow shown in the photo is b characterized by its rough, jagged surface. It's from the Kapoho Eruption in Hawaii, where aa lava flows destroyed the town, making option 2 the correct answer.
Step-by-step explanation:
The lava flow in the foreground of the photo is an example of a type of lava flow known as aa. The aa lava flow is characterized by a rough, jagged, and clinkery surface, making it quite distinctive from pahoehoe lava which has a smooth and ropy surface.
The photograph's description explains that during the Kapoho Eruption in Hawaii, the town was destroyed by aa lava flows, suggesting that the correct answer to the student's question is option 2. aa. This type of lava flow occurs when the basaltic lava is more viscous and cools rapidly which creates its rough surface texture. A basaltic eruption typically produces fast-moving basaltic lava which can cover significant distances.
As for pillow lava, it forms underwater when lava erupts on the ocean floor, creating rounded, pillow-shaped structures as it cools rapidly in water. Ash, on the other hand, is composed of fine particles of volcanic rock ejected into the atmosphere during explosive volcanic eruptions, rather than a type of lava flow