Answer:
Option (B)
Explanation:
Gneiss is a metamorphic rock which forms due to the extremely high pressure and temperature condition. It is characterized by the coarse and medium-sized grains and there is the presence of alternating dark and light-colored bands on it. The light color band contains felsic minerals such as feldspar, quartz and the dark band contains mafic minerals such as biotite, hornblende, garnet. It is a very high-grade metamorphic rock. These characteristics helps in identifying a gneissic rock.
Thus, the geologist found a gneissic rock.
Hence, the correct answer is option (B).
