The metric system is deliberately designed to be simple arithmetically and yet capable of_______ expansion as it becomes necessary to _______ new units of measure.
A) confusing...record
B) mathematical memorize
C) rigid...discard
D) indefinite...invent
E) limited...correct

Question

Quizplus · Accepted Answer

The use of the phrase 'and' yet implies that the first missing word must mean the opposite of the phrase 'simple arithmetically'. Among the choices for the first missing word this only the phrase 'capable of indefinite expansion' that has this meaning. Its pair word 'invent' completes a logical sentence. So, D is the answer.

The Metric System Is Deliberately Designed to Be Simple Arithmetically