<span>b. spice
</span><span> The product that was commonly traded along the Silk Road were spices. Spices were produced in countries far away from Europe and they were very expensive, both because the production was limited and because the trip to collect them was dangerous. The Silk Road linked Asia and Europe via land for many centuries before the age of Discoveries. </span>
Because it can be very reliable
A historical source that might distort the information by putting a strong preference or viewpoint is considered a biased source.
<h3>What is a historical source?</h3>
A historical source is the ones that existed in ancient history like the artifacts, sculptures, coins, etc.
When the point of view or opinions in respect of a historical source deforms the provided information, then that source is regarded as a biased source. This is the source that has differentiated opinions or is defined in inappropriate language.
Therefore, the biased source is the one that portrays a strong opinion which ultimately distorts the original information.
Learn more about the biased source in the related link:
brainly.com/question/4357533
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