Answer:
Options One, Two, and Five are the correct answers.
Explanation:
Posting on a personal blog is not wrong by itself, but it could also mean that there are no standards for the evidence provided in the blog (it could come from just personal deductions or experiences), and it could also be provided as the one an only truth, turning it into a discardable source.
If the author does not have background or education on the field, he or she cannot talk about something that is very specialized, such as the latest discoveries in cancer treatment, due to the terminology or specific knowledge that is required to understand the complete picture, such as parts of the body or how cells work.
Finally, if the paper is looking for the latest discoveries, the early 1900s is the opposite from what is being required.