听力原文： Unwanted sound, or noises produced by airplanes, traffic, or industrial machiner

y, is considered a form. of pollution. Noise pollution is at its worst in densely polluted areas. It can cause hearing loss, stress, high blood pressure, sleep loss, distraction, and lost productivity.

Most humans can hear sounds between 20 and 20,000 hertz, while dogs can hear high-pitched sounds up to 50,000 hertz. While high frequency sounds tend to be more hazardous and more annoying to heating than low frequency sounds, most noise pollution damage is related to the intensity of the sound. Measured in decibels, noise intensity can range from zero, the quietest sound the human ear can detect, to over 160 decibels. Conversation takes place at around 40 decibels, a subway train is about 80 decibels, and a rock concert is from 80 to 100 decibels. The intensity of a nearby jet taking off is about 100 decibels. The threshold for pain, tissue damage and potential hearing loss in humans is 120 decibels. Long lasting, high intensity sounds are the most damaging to hearing and produce the most stress in humans.

Solutions to noise pollution include adding insulation and sound proofing to doors, walls, and ceilings; using ear protection, particularly in industrial working areas; planting vegetation to absorb and screen out noise pollution; and zoning urban areas to maintain a separation between residential areas and zones of excessive noise.

According to the passage, intense noise pollution may NOT cause ______.

A．hearing loss

B．high blood pressure

C．lost productivity

D．poor appetite