What will happen if there is no gravitational pull in earth

A lack of gravity would eventually take its toll on our very planet, writes Masters. "Earth itself would most likely break apart into chunks and float off into space." ... Without the force of gravity to hold it together, the intense pressures at its core would cause it to burst open in a titanic explosion.

the correct answer is 4) heat and pressure

metamorphic rocks arise from transformation of existing rocks types, in a process called metamorphism. during metamorphism the original rock(prolith) change into metamorphic rock by heating (150-200c) and pressure of more than 1000 bar. the original rock can be sedimentary, igneous, or existing metamorphic rock.