What is an angular unconformity? A: The rock layers are angled to the horizontal ones above. B: Areas in the rock layer that are missing. C: Represents periods of erosion. D: Separates metamorphic or igneous rock layers from sedimentary.

Angular unconformity is an unconformity where horizontally parallel strata of sedimentary rock are deposited on tilted and eroded layers, producing an angular discordance with the overlying horizontal layers. The whole sequence may later be deformed and tilted by further orogenic activity.