The answer to #1 should be mountain-building. Water cannot be affected in weathering, and neither can seafloor spreading. Volcanoes, however, could, but the most likely choice they teach in school would be mountain building. However, if it was asking about erosion, the answer would be water.
The answer to #2 is sedimentary. Look at the problem this way:
During erosion, sediments are eroded from the rock. Deposition then carries the sediments, and eventually they can build a sediment formation, turning into a rock. Also, metamorphic rocks, are heated and formed by magma, which is then cooled. Igneous rocks are made by extreme heat and pressure.
The answer to #3 is erosion.
