It's past tense, so the answer is was not
All the solutions are in some way referred to in the text, but I would say this aspect was the tipping point:
<span>C.A classmate's mother would not let Wind-Wolf play at her house because he was an American Indian.</span>
3: The author is depicting the men's return to earth after they have lived with the Selenites
Undesirable situation that occurs when a device or system attempts to perform two or more operations at the same time, but because of the nature of the device or system, the operations must be done in the proper sequence to be done correctly.
