Question

Water in which form is considered as single most important agent?

(a) Solid

(b) Liquid

(c) Gaseous

(d) Solid and liquid

The question was posed to me by my school principal while I was bunking the class.

Origin of the question is Metamorphism and their factors topic in chapter The Study of Rocks of Engineering Geology

Answer 1

Correct option is (c) Gaseous

Explanation: Water in the form of steam is considered the single most important agent. The water may be present in the minerals as water of crystallization or simply as pore fluid or it may be supplied externally by magmatic bodies.