Question

Interbreeding two different species of lovebirds produces offspring that are unable to build a nest after they mature because they lack the appropriate innate knowledge needed to carry the nesting materials and build a nest. This limits genetic mixing between the species due to:

Answer 1

I believe the correct answer would be behavioral isolation. It is an isolating mechanism where two populations or species cannot mate because of the differences in their courtship and mating behavior.  It is also called as ethological isolation.