GMAT Critical Reasoning (CR) | Re: Shelby Industries manufactures and sells the same gauges as

Shelby Industries manufactures and sells the same gauges as Jones Industries. Employee wages account for forty percent of the cost of manufacturing gauges at both Shelby Industries and Jones Industries. Shelby Industries is seeking a competitive advantage over Jones Industries. Therefore, to promote this end, Shelby Industries should lower employee wages.

Which of the following, if true, would most weaken the argument above?
(A) Because they make a small number of precision instruments, gauge