Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction. this is an example of speciation.

The correct answer would be behavioral.

Behavioral reproductive isolation is one of the methods that lead to speciation.

It is a type of prezygotic isolation in which species are isolated through differences in the mating signals and rituals.

For example, a particular pattern of dance, songs et cetera.

Similarly, jumping of a male bird in the opposite direction would not be recognized by the female bird due to which they would not be able to interbreed.