Were did the code talkers train

On May 5, 1942, 29 Navajo men arrived at the Recruit Depot in San Diego for basic training. That was followed by intensive courses in transmitting messages and radio operation at the Fleet Marine Force Training Center at Camp Elliot. The 29 recruits developed the code with communications personnel during this training.

( G O O G L E )

either d or b, i'm not to sure. but my gut tells me it's prob going to be b

the answer to your question is

transform it from an expensive luxury to a mid-priced good