Which choice is common knowledge and could be used in a research paper without crediting the source? a. financial data published in the newspaper b. the freezing temperature of water c. the copyrighted blueprint for a building d. the opinion of a citizen

B. the freezing temperature of water.

This is the option that can be considered common knowledge. The author of a piece that contains this information does not need to provide his source, because he can assume most people would be aware of this information. If a reader is not aware of it, he can look it up, and as there is consensus on this piece of information, he will find the same information in a variety of easily accessible sources.

to show that social not the correct answer!

it is used to emphasize the word or sentence.