Answer:
The answer is B. The opinions may provide clues to the source's feelings and possible bias.
Explanation:
Primary sources are the main source of data and information for historical research, however, these sources provide more than only facts, such as dates and names, they are also charged with opinions and other subjective data. Historians must consider this subjective data, to further understand the source's feelings, political views, etc., not only to identify any possible bias, but also because subjective data can also be a valuable source of information to characterise society in any given time and space.
