A、They are social marine animals. B、They call for help when they are in danger. C、They hunt food alone and independently. D、They

For the second time in only two weeks, a large group of pilot whales has died after stranding themselves in Sandy Cape on the remote western coast of Tasmania, Australia.
    (32) Due to the area’s remote location, rescuers were unable to reach the scene until a day after the stranding was reported. (33)Still, they managed to save 32 whales. Just one week earlier, more than 50 whales died after becoming stranded on another nearby beach.
     Because Tasmania is along the whale migration route to and from Antarctic waters, strandings there are not uncommon. According to Tasmania’s Department of Primary Industries and Water, 75 whale stranding incidents have occurred since 1900, several of which involved more than 200 animals.
    (34) Pilot whales are among the most social marine mammals, often traveling in pods that include hundreds of individuals. Although these strong social bonds help the whales survive, their herding behavior can also lead to their death --- (34) if one whale is in danger, it will signal the other members of the pod to follow.
     Some scientists believe that the whales become stranded when they are forced to chase prey too close to shore. Predators like killer whales can also cause" panic" within a whale pod, scaring them and" herding" them toward the shoreline. Other researchers have suggested that the whales’ echolocation system may not detect gently sloping coastlines. More controversial theories attribute whale stranding to military sonar and changes in the Earth’s magnetic field, which could interfere with the animals’ ability to navigate. (35) But none of these theories have yet been proven, and the reason behind mass whale strandings is still a mystery.