Visiting patients usually send a bunch of flowers. However, it has been reported in a country that the water for raising flowers in hospital vases may contain a lot of bacteria. Flowers will compete for oxygen with patients at night, and may also affect the work of electronic equipment in the ward. This caused people to panic about flowers. Some hospitals in the country even banned the display of flowers in wards. Although it was later confirmed that flowers did not cause more patients to be infected, and the authority also clarified that no infection cases were related to the plants in the ward, this did not reduce the hospital's aversion to flowers.
Which of the following options does not allay the hospital's concern about flowers?
Studies have proved that the impact of flowers on the air in the ward is negligible