Answer:
The use of dialect in speech.
Step-by-step explanation:
Realism is a literary period when the more popular form of Romanticism was done away with and the tendency to depict real life situations began to be more focused on. This literary era refutes the 'imaginary, romanticized and sugar coating' way of literature that was the focus in the Romantic period.
The trend of using heroic characters has been in used since the classics, in the epics while the use of imaginary settings and tragic themes have also been in used even before the 19th century. Romanticism has been more easily specified by it's use of the 'romanticized, imaginary, fairy-tale' themes which also have tragic themes in them. But the actual tendency to focus on the true and realistic nature of humanity began to progress with the start of realism during the mid 19th century. Thus, the technique which originated in the realist era will be the use of dialect in literature.