Challenging exhaustive note taking
time-consuming lab work
I'd say D, because that seems like a good writers strategy. To give information centered around the narrative and theme. Otherwise, A.
Print sources include any material that is found in print: a traditional book, magazine, or newspaper. In these times of multiple electronic sources, it can be confusing to determine which sources are identified as print. Even if you find a source in an online database, if there is a print (paper) copy somewhere, then you can list this source as print.
