What happens when two waves of the same frequency and amplitude meet in phase?

They cancel each other out resulting in a destructive interference

They combine to form a wave double the amplitude, resulting in constructive interference

They produce a wave with zero amplitude

They produce a wave with the same amplitude as the individual waves

When two waves of the same frequency and amplitude meet in phase, they align perfectly at their peaks and troughs.

This results in constructive interference, where the amplitudes of the waves add together.