The noise that affects sea creatures conies from the following EXCEPT [originalt

Some scientists say that animals in the ocean are increasingly threatened by noise pollution caused by human beings.
    The noise that affects sea creatures comes from a number of human activities. It is caused mainly by industrial underwater explosions, ocean drilling, and ship engines. Some scientists have proposed setting a noise limit of 120 decibels in oceans. They have observed that level can frighten and confuse whales.
    A team of American and Canadian scientists discovered that louder noises can seriously injure some animals. (15) The research team found that powerful underwater explosions were causing whales in the area to lose their hearing, This seriously affected the whales’ ability to exchange information and find their way. Some of the whales even died. The explosions had caused their ears to bleed and become infected.
    Many researchers whose work depends on ocean sound object to a limit of 120 decibels. They say such a limit would mean an end to important industrial and scientific research. (16) Scientists do not know how much and what kinds of noises are harmful to ocean animals. However, many scientists suspected that noise is a greater danger than they believed. They want to prevent noises from harming creatures in the ocean.