The two correct responses that best support the inference that honeybees—not bumblebees—are responsible for infecting the studied flowers are:
- All of the honeybees researchers collected were infected with both viruses.
- More than 90 percent of bumblebees collected close to apiaries were infected with black queen cell virus.
The first response indicates that commercial honeybees are carriers of the viruses, suggesting a potential source of infection. The second response highlights the high prevalence of infection in bumblebees near apiaries, which implies that the proximity to honeybees might play a role in the transmission of the viruses, although it notes that the infection levels elsewhere don't differ in terms of abundance.