Answer & Explanation
Option: Whale songs are typically below 4 kHz in frequency (human hearing range is between 20 Hz to 20 kHz), thus being inaudible to human ears.
Explanation:
In a paper published in the journal Endangered Species Research, authors described a new whale song, suggesting the existence of a population that was previously unknown. Researchers analysed recordings from three locations in the western Indian Ocean from where they discovered the unique whale song. Whale songs can last between 6-35 minutes, and some individual whales have been found to sing for 22 hours. Whale songs are typically below 4 kHz in frequency (human hearing range is between 20 Hz to 20 kHz), thus being inaudible to human ears.
