The correct answer is option 3, the Blue whale. Among the given options, blue whales give birth to the biggest babies. Blue whales are the largest animals on Earth and can grow up to 100 feet long. The average weight of a blue whale baby is around 2.7 metric tons, which is much larger than any other animal`s offspring.

Let`s look at the other options to understand why they are not the correct answers. Option 1, the Elephant, gives birth to relatively large babies, weighing around 200 pounds. However, they are significantly smaller than blue whale babies. Option 2, the Rhinoceros, also gives birth to relatively large babies, but they are not as big as blue whale babies. Option 4, the Hippopotamus, gives birth to babies that are smaller than both elephants and rhinoceroses.

In summary, while elephants, rhinoceroses, and hippos give birth to relatively large babies, the blue whale surpasses them all by giving birth to the largest babies.