Choose the most appropriate word from the following options to fill in the blank (A), as highlighted in the given passage.

Explanation

Among the given words, ‘measure’ is the most appropriate word to fill in the blank (A). The concerned sentence also states that annual energy consumption per capita is a useful measure of a country's progress in terms of electric power development. Hence, option (c) is the right answer choice. (a) component- part or element of a larger whole, especially a part of a machine or vehicle. (b) factor- a circumstance, fact, or influence that contributes to a result. (c) measure- a standard unit used to express the size, amount, or degree of something. (d) impediment- a hindrance or obstruction in doing something. (e) trigger- cause (a device) to function.