The difference(s) between the Grand Canyon and Valles Marineris is/are: (a) the Grand Canyon was formed by water, but Valles Mar
ineris was not. (a) Valles Marineris is much longer than the Grand Canyon. (c) Valles Marineris is much wider than the Grand Canyon. (d) Valles Marineris has large volcanoes near it. All of the above
