Which of the following is an example of gene flow? selective breeding of dairy cows to produce animals that can live in tropical climates and yield higher volumes of milk the carriage of seeds between two separate urban forests by wildlife such as squirrels and rats that travel back and forth between the two cross pollination by migrating honey bees between two geographically separate but genetically identical cotton fields the passage of a recessive disease-causing allele from one generation to the next without the physical appearance of disease the introduction of burmese pythons, with no known predators or compatible mates, into the florida everglades

Gene flow is the movement of genes from one population to another population.

Explanation:

Selective breeding of dairy cows to produce animals that can live in tropical climates and yield higher volumes of milk. (There is no gene flow in this example because the organisms being breed belong to 1 population)

The carriage of seeds between two separate urban forests by wildlife such as squirrels and rats that travel back and forth between the two. (This could be an example of gene flow because if those seeds germinate, grow and produce flowers their genes could be mixed up during pollination)

cross pollination by migrating honey bees between two geographically separate but genetically identical cotton fields. ( this is clearly an example of gene flow. Bees are transferring genetic material between populations)

the passage of a recessive disease-causing allele from one generation to the next without the physical appearance of disease. (because the genes are moving from one generation to the next one, this implies only no population, so there is no gene flow here)

The introduction of Burmese pythons, with no known predators or compatible mates, into the Florida Everglades. (there is not an exchange between python populations, only a new species is being introduced)