Increased seismicity (# quakes per day) and increased emission of gases (like carbon dioxide and sulfur dioxide) are two signs that can signal that a volcanic eruption is imminent. what is the most likely cause of these two precursors

Increased seismicity and increased gas emission means the building of pressure.

Explanation:

Various factors like the earthquakes, tsunamis, gas release, and the mid slides and the occurrences of the avalanches indicates that the ground deformations and the build of a pressure cell that is going to blow out form the weakest part of the earth. It can be seen through the thermal motioning systems, like those of the satellite imagery and the hydrological studies of tides and the ocean currents. Also the mass movement and raptures, rocks fall and the debris slides.

"pacesetter of the south," comma inside the quotes

Answerscripps institution of oceanography; i believe this is correct plz check first good luck;