Question

question 4
1 pts
a scientist named dr. burkholder hypothesized that the dinoflagellate pfiesteria was associated with the massive die - offs of fish in north carolina rivers. subsequent observations supported her hypothesis. which of the following observations would support that hypothesis?
pfiesteria was shown to be capable of living within the climatic ranges of north carolina.
a virulent toxin was isolated from pfiesteria cultures grown in the laboratory.
a predicted increase in pfiesteria populations coincided with a fish die - off.
new observations revealed that pfiesteria could kill laboratory fish.

Explanation:

The hypothesis is that Pfiesteria is associated with fish die - offs in North Carolina rivers. A predicted increase in Pfiesteria populations coinciding with a fish die - off directly links the presence of Pfiesteria to the fish die - off event in the natural river setting, providing strong support for the hypothesis. Just being able to live in the climate, isolating a toxin in the lab, or killing lab fish does not as directly connect it to the mass die - offs in North Carolina rivers.

Answer:

A predicted increase in Pfiesteria populations coincided with a fish die - off.