I have two questions; all are multiple-choice answers. Two of them are based on what data collection method the articles used. I will post a link to the articles. https://www.sciencedirect.com/science/article/pii/S2667010022000646 (Click on View PDF on the top) 1. The data collection method used by the researchers of the article Lethality of resistant/virulent environmental vibrio cholerae in wastewater disease: An evidence of emerging virulent/antibiotic-resistant-bacteria contaminants of public health concern was: A) observation and interviews B) systematic literature review C) secondary data collection D) primary data collection E) theoretical https://www.sciencedirect.com/science/article/pii/S0160412021006723?via%3Dihub 2. The data collection method used by the researchers of the article Environmental contamination in a high-income country (France) by antibiotics, antibiotic-resistant bacteria, and antibiotic resistance genes: Status and possible causes was: A) observation and interviews B) systematic literature review C) secondary data collection D) primary data collection E) theoretical .