To determine that triangles \( \triangle OPQ \) and \( \triangle RST \) are congruent using the SSS (Side-Side-Side) Congruence Theorem, we need to show that all three corresponding sides of the triangles are congruent.
From the information provided in your description, we know that:
- The sides \( PQ \) and \( TS \) are marked with two dashes (indicating they are congruent).
- The sides \( OP \) and \( RS \) are marked with one dash (indicating they are congruent).
However, to use the SSS theorem, we also need to know the length of the third pair of corresponding sides:
- The triangle \( OPQ \) has sides \( OP \), \( PQ \), and \( OQ \).
- The triangle \( RST \) has sides \( RS \), \( RT \), and \( ST \).
Since the sides \( OP \) and \( RS \) are already congruent (one dash), and \( PQ \) and \( ST \) are congruent (two dashes), we need information about one of the remaining sides to apply SSS properly.
Thus, you need to know either:
- \( OQ \) must be congruent to \( RT \), or
- \( OQ \) must be congruent to \( TR \), or
- \( OQ \) must be congruent to \( RS \).
Since the most appropriate choice from your options would be relating the third side, we would conclude that:
We need: \( OQ \cong RT \) (as this directly corresponds to completing the SSS criteria).
Based on your options, the response would be: \( OQ \cong RS \)