Ask yourself three questions:
1. Which sign marks the nominative of the sound feminine plural? — ḍamma.
2. Which sign marks its accusative? — kasra.
3. If accusative and genitive look alike, how can you distinguish them? — Examine the governor and syntax.
Now explain aloud the difference between رَأَيْتُ طَالِبَاتٍ and مَرَرْتُ بِطَالِبَاتٍ.