Consider Two Identical and Symmetrical Wave Pulses on a String

Multiple Choice

Consider two identical and symmetrical wave pulses on a string.Suppose the first pulse reaches the fixed end of the string and is reflected back and then meets the second pulse.When the two pulses overlap exactly,the superposition principle predicts that the amplitude of the resultant pulses,at that moment,will be what factor times the amplitude of one of the original pulses?

A) 0
B) 1
C) 2
D) 4