(a) Sedimentary rock
(b) Metamorphic rock
(c) Igneous rock
(d) Volcanic rock
Ans :- (a) Sedimentary rock

Explanation :-
Sandstone is a sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm)
silicate grains. Sandstones make up about 20 to 25 percent of all sedimentary rocks. Most sand stone composed of quartz or feldspar because they are most resistant minerals to weathering process.