Which type of pluton is described as being flat and tabular, intruded parallel to the layering of the host rock?

The type of pluton that is flat and tabular, intruded parallel to the layering of the host rock, is known as a sill. Sills form when magma intrudes between existing layers of sedimentary rock or other types of layered rocks, creating a horizontal sheet. This characteristic parallel orientation to the host rock's layering distinguishes sills from other plutonic formations.

In contrast, dikes are typically vertical or steeply inclined and cut across the layers of the host rock rather than following them. Laccoliths are dome-shaped intrusions that create bulges in the overlaying strata, requiring a substantial amount of magma to form. Batholiths, on the other hand, are large, massive intrusions that typically extend over a wide area and are formed from the amalgamation of multiple sills and other smaller intrusions.

Understanding these distinctions helps to reinforce the knowledge regarding geological formations and the processes by which magma interacts with pre-existing rock layers.