The Serbian language is the mother tongue of 84.4 percent of the population of Serbia according to the latest numbers published by the Serbian Republic Institute of Statistics.

After Serbian, the most represented mother tongues are Hungarian, 2.6 percent, Bosnian, 2.2 percent, Romani, 1.2 percent, and Albanian, 1.0 percent.

We can only guess that many Roma simply wrote their mother tongue is Serbian (or Hungarian).

• Srpski jezik maternji za 84,4 odsto građana Srbije, 81,1 odsto stanovnika pravoslavci. In: Politika. 19.06.2023. https://www.politika.rs/sr/clanak/558213/srpski-jezik-pravoslavlje-vera-srbija