Which of the Following Low-Intensity Stimuli Would Be Most Difficult

Multiple Choice

Which of the following low-intensity stimuli would be most difficult to habituate to, and why?

A) The sight of a mosquito due to common bug phobias (that you do not have)
B) The humming of an air-conditioner because it is not a natural sound
C) The sound of running water because it is a natural sound
D) A buzzing mosquito because it is a natural threat