10
QuizMultiple Choice

Volcanoes

Question 10 • PARTA - EVP: PGCPS BIOGEOCHEM CR (FALL2026) - 798113

A volcano erupts, and lava flows down a mountainside. Which statement best describes this eruption?

Answer
A
This is a quiet eruption caused by low-viscosity magma.
B
This is an explosive eruption caused by high-viscosity magma.
C
This is a quiet eruption with lava spewing out violently.
D
This is an explosive eruption during which gases bubble out gently.

Explanation

Lava that flows down a mountainside is characteristic of a quiet eruption. Low-viscosity magma is runny, so it can flow easily and lets gases escape without building up enough pressure for a violent explosion. Thus, the best choice is “a quiet eruption caused by low-viscosity magma.”

AI-written and checked against the verified answer.