Researchers conducted a follow-up survey of 9 people wearing contact lenses and 11 people without contact lenses, and found that compared to people without contact lenses, some types of bacteria on the surface of the eyes of people wearing contact lenses The average increase was twice as high as that of the column. The composition of the flora on the surface of the eyeballs of the two groups was also different, and a bacteria called pseudomonas that caused corneal ulcers was more common in the eyes of people with contact lenses. Changing the flora in the eye is more likely to cause eye infections. Which of the following, if true, would best support the above argument. ['Since the emergence of soft contact lenses, the prevalence of corneal ulcers has increased significantly.', 'To avoid corneal ulcers, pay close attention to eyelid and hand hygiene and check regularly.', 'People with contact lenses, although the eye flora has changed, rarely have complications.', 'The sample size of this study is too small, and we should still be cautious about the findings.']