humus, crystal, and ore water, weathered rock, and humus water, metamorphic rock, and crystal metamorphic rock, ore, and weathered rock
I gave my students this multiple choice question: A student is asked to make soil using the following substances: water, ore, humus, crystal, weathered rock, and metamorphic rock. Which combination of these substances should the student choose?

Only one answer is correct among these 4 choices:
- humus, crystal, and ore
- water, weathered rock, and humus
- water, metamorphic rock, and crystal
- metamorphic rock, ore, and weathered rock

Could you tell me which one is correct?

water, weathered rock, and humus