How many inches is one mill equal to?

The correct conversion of one millimeter to inches is approximately 0.03937 inches. When expressed in fractions, this value is very close to 1/1000 of an inch. Therefore, understanding this relationship highlights the fact that one millimeter is indeed equivalent to 1/1000 of an inch.

To provide further context, the other fractional options do not align with the indicated conversion. For example, 1/100 inch is larger than a millimeter, while 1/500 and 1/2000 of an inch also do not reflect the proper conversion rate between these two units of measurement. This reinforces the fact that option B correctly represents the relationship between millimeters and inches.