Final answer:
The coincidence of rays OM, ON, and OP at time t=0 indicates constructive interference.
Step-by-step explanation:
The coincidence of rays OM, ON, and OP at time t=0 indicates constructive interference.
In the context of waves, constructive interference occurs when two waves meet and their amplitudes add up, resulting in a wave with larger amplitude. This can happen when the waves are in phase, meaning their peaks and troughs align. When the peaks of two waves coincide, the resultant wave will have a greater amplitude. This is observed when rays OM, ON, and OP coincide, suggesting constructive interference.