The factor that could have led to this conclusion is : ( C ) The paper showed signs of bias and lacked proper citations.
Importance of citations
The paper published by the historian lacked proper citations from renowned historians to back up his research, therefore the paper will be filled with signs of bias and this will make the readers/scholars conclude that his research was not reliable enough.
When publishing a paper about a known personality proper citations are required to backup your research so the the readers will find your paper reliable.
Hence we can conclude that The factor that could have led to this conclusion is The paper showed signs of bias and lacked proper citations.
Learn more about proper citations : https://brainly.com/question/8130130
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