(a) schist
(b) Limestone
(c) Sandstone
(d) Granite

Ans : – (a) schist

Metamorphic rocks – Metamorphic rocks are formed igneous or sedimentary rocks as a result of the action of the earth movement, temperature changes, liquid pressure etc.
Exp.- Marble, Gneiss, quartzite, slate, schist, serpentine etc.