Which type of rock forms in a similar manner as obsidian but at a slower rate?

Question

A. . schist, which forms under extreme heat and pressure

B. conglomerate, which forms when different-sized sediments cement together

C. gypsum, which forms when water evaporates and leaves behind minerals

D. granite, which forms as magma cools deep underground

Answer 1

C. gypsum, which forms when water evaporates and leaves behind minerals