What is most likely to be considered plagiarism?

Using materials from a source without proper citation is most likely considered plagiarism because it involves taking someone else's ideas, words, or research and presenting them as your own. This act violates academic integrity and ethical standards in research, which emphasize the importance of giving credit to original authors and sources. Proper citation not only acknowledges the contributions of others but also allows readers to verify the information and further engage with the research. Plagiarism undermines trust in the research process and can lead to severe consequences in both academic and professional settings.

In contrast, tampering with research equipment typically falls under issues related to scientific misconduct rather than plagiarism. Adding extra data points without proper justification might relate to data fabrication or falsification, which also do not directly pertain to the misappropriation of someone else's work. Reporting results of inaccurate statistical tests pertains to dishonesty in data analysis rather than the issue of presenting someone else's work without credit.