Answer:
A). An exploration of ideas.
Explanation:
An essay is illustrated as the written piece of work that involves expedition of a specific topic or subject which is often accomplished by the inclusion of the author's personal remarks based on his/her opinions or point of view.
As per the question, an essay could be regarded as the 'exploration of ideas' which is inclined towards analysis and interpretation to present a detailed argument with a conclusion(including authorial remarks). It could be either formal or informal with each having a purpose to serve. It is chiefly inclined towards exploring a specific idea in different aspects that aids to examine and evaluate these aspects that how each aspect contributes to the whole. Thus, option A is the correct answer.
