The extreme size of volcanoes on Mars indicates that
A) Mars has a much thinner crust than Earth.
B) water once flowed in streams on Mars.
C) large horizontally moving crustal plates have not formed on Mars.
D) a and c
E) a,b,and c

Question

Quizplus · Accepted Answer

Mars's large volcanoes suggest that the planet lacks the tectonic activity seen on Earth, which would otherwise redistribute volcanic material and limit the size of individual volcanoes.

The Extreme Size of Volcanoes on Mars Indicates That