The most plausible explanation for the diagonal line disrupting the horizontal layers of sedimentary rock is:
B. a long time after the layers of rock formed, the tectonic plate experienced a fold or a tilt. This caused the dramatic shift seen in the layers.
This is because sedimentary rock layers can be altered by geological processes such as tectonic forces, which can cause folding or tilting. A diagonal line suggests that the layers were once horizontal but were later subjected to stress that caused them to shift, which is common in areas with tectonic activity. The other options either misinterpret the processes involved in sedimentary rock formation or do not appropriately account for the geological processes that can lead to the observed features.