Fact 1: Extreme heat and pressure change rock into metamorphic rock. Fact 2: Sedimentary rock changes into a different form when it undergoes heat, pressure or other forces. Given the two facts above, what makes sedimentary rock turn into metamorphic?

Options are:
(1). crust
(2). erosion
(3). thrust
(4). wind
(5). two
(6). coal
(7). calcite
(8). Force
Answer:
(8).