Which is an example of irresponsible use of a source?

Question

Nathan copies content from his textbook into his essay without using quotation marks or crediting the author.
Julia interviews a local librarian and paraphrases the conversation in her essay.
Reynaldo protects his login information for the academic database.
Cynthia decides not to use a source from an online blog because she cannot verify the author or their expertise.

Answer 1

An example of irresponsible use of a source is:

Nathan copies content from his textbook into his essay without using quotation marks or crediting the author.

This action constitutes plagiarism because he is using someone else's words and ideas without giving proper credit.