Answer:
A). How many people spoke Navajo before World War I ?
B). Was the US government able to figure out other countries’ codes ?
Step-by-step explanation:
The above questions would assist in enhancing the readers' ability to comprehend that the military leaders' dread of code not being effective to be used for the second time. The question regarding the 'number of people speaking Navajo prior to WWI' would provide a hint to the readers that they are fearing that the code might be decoded by an outsider(who knew the language) or the students who were sent for learning American Indian languages. The next question regarding the US government's success in decoding the codes of other countries further substantiates that they had an innate dread of their first code being decoded already by them(US government). Thus, options A and B are the correct answers.