While conducting fieldwork studies, a pupil collected a set of strike and dip measurements after dipping sedimentary layers.
If he had used a geological compass, what could be the most probable cause of error in the measurement recorded?
A. The variation of the magnetic field of the earth.
B. The gravity waves that emanate from two black holes merging.
C. Errors arising from irregularities when measuring bedding surfaces.
D. Solar magnetic storms.