Which of the statements below best describes the relationship between a star's mass and its duration on the main sequence? A) The lower the mass, the shorter the main sequence lifetime.
B) Main sequence lifetime doesn't depend on mass, but rather the volume of the star i. e. Red Giants vs. White Dwarfs
C) The higher the mass, the shorter the main sequence lifetime

answer: the metamorphic rocks are formed when they are exposed to high pressure and high temperatures. this happens when one of the earth's plates comes in contact with the other plate by traveling in opposite directions, straight into each other or slipping under one another. the friction that is caused by this activity results in   melting of rocks and when it cools they are known as metamorphic rocks. this process needs a controlled amount of pressure and temperature otherwise it may turn into magma.