None of this is any more or less precise than others. However, it is recommended to use metric units (meters, centimeters, millimeters) etc. world-wide, to use a common standard. Also, because the metric system simplifies all sorts of calculations.
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The smallest unit among those choices is the millimeter, so if you weren't using decimal point measurements with the other units, then that one would be more precise... but people can use precise measurements with all of these, so the answer above is correct. The imprecision only comes in the way that we use them... if we say "oh, about 5 inches" instead of saying "4.995 inches."
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