The first thing we will do for this case is to define the scientific notation:
It is a way of writing numbers that accommodate values too large or too small to be written in a conventional manner.
A number written in scientific notation follows the following pattern:
Where,
The number m is called "mantissa" and e the "order of magnitude"
The smallest length then, is one that has the smallest order of magnitude:
Answer:
The measurement of length that is the smallest is:
option A