Please help! Will mark brainlist

The difference(s) between the grand canyon and valles marineris is/are: (a) the grand canyon was formed by water, but valles marineris 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

After considering options, a student using the problem-solving process should next

Quiero una redaccion de yo soy medico y que tenga 10 lineas