KeerthanaPosted on I had invited (1)/ all my sister-in-laws (2)/ to my son’s birthday party. (3)/ No error (4) aout bthrough coff dacross Answer : Option BExplanation : Sister-in-law Ÿ Sisters-in-law (Plural) Hence, all my sisters-in-law should be used here. Rate This:NaN / 5 - 1 votesAdd comment