In October on the east coast of Australia migrating humpback whales pass very close to the shore. With the help of Max Egan, we went to film them near Byron Bay. It was extremely exciting to spot the little puffs of spray on the horizon. When migrating, the whales can be traveling at speeds of about 12km/h and can dive under anywhere between five and forty minutes, but with many years of experience Max usually guided our boat to exactly the right place to provide us with amazing sighting. As the whales break the surface like submarines , the water spills off their broad dark backs and huge tails. Then, with a powerful down stroke, they dive back into the depths of the sea, leaving just a smooth glassy patch of water or "footprint" on the surface to show where they had been. One day we had traveled up and down the shore and far out to the sea in search of whales, but the horizon was deserted. There was no report of whales in the area so we decided to test out Max's new, highly sensitive hydrophone and the result was astonishing. As soon as the hydrophone was in the water, we found ourselves listening to the most beautiful  voices. What may have seemed like a vast empty ocean was filled with the singing of whales. It is the males which sing, as they migrate between feeding and breeding grounds. No one knows for sure what the purpose of these songs is, whether they are love songs to the females or warnings to other males to stay away. It was thought that each population of humpbacks had its own song which remained regular but recent findings suggest that the whales appreciate a memorable tune and quickly adopt any new songs they hear. The writer's main purpose of looking for whales is  _  .
carrying out research on whales studying the beautiful songs of whales making films about whales hunting whales for research
Question: In October on the east coast of Australia migrating humpback whales pass very close to the shore. With the help of Max Egan, we went to film them near Byron Bay. It was extremely exciting to spot the little puffs of spray on the horizon. When migrating, the whales can be traveling at speeds of about 12km/h and can dive under anywhere between five and forty minutes, but with many years of experience Max usually guided our boat to exactly the right place to provide us with amazing sighting. As the whales break the surface like submarines , the water spills off their broad dark backs and huge tails. Then, with a powerful down stroke, they dive back into the depths of the sea, leaving just a smooth glassy patch of water or "footprint" on the surface to show where they had been. One day we had traveled up and down the shore and far out to the sea in search of whales, but the horizon was deserted. There was no report of whales in the area so we decided to test out Max's new, highly sensitive hydrophone and the result was astonishing. As soon as the hydrophone was in the water, we found ourselves listening to the most beautiful  voices. What may have seemed like a vast empty ocean was filled with the singing of whales. It is the males which sing, as they migrate between feeding and breeding grounds. No one knows for sure what the purpose of these songs is, whether they are love songs to the females or warnings to other males to stay away. It was thought that each population of humpbacks had its own song which remained regular but recent findings suggest that the whales appreciate a memorable tune and quickly adopt any new songs they hear. The writer's main purpose of looking for whales is  _  .
A. carrying out research on whales
B. studying the beautiful songs of whales
C. making films about whales
D. hunting whales for research
Answer: