What was the right answer to these science questions?

Jenny S is right and i will explain the third question. well it depends either the rocks are of what type if its lime stone then i don't think so that it will be rounded because limestone always dissolves in water if it is sandstone then a sandstone can break a part but it can never be rounded. and if its shale then hay it will be plate like but not rounded. but if you are talking about the size i.e gravels, sand or silt. then gravels are rounded and they are sediments not a sedimentary rock. because they have different mineralogy and origin. and the picture was showing gravels then water is the best answer but if its not gravels then the given rock is not a sedmentry rock. and hay below links may helps you.