Read the following passage and answer the questions given after it.

The giraffe is the tallest land mammal alive, its long legs and neck contributing to its impressive stature. Males can be up to 18ft (5.5m tall), females a little less.

In the wild, these beautiful creatures stretch their necks beyond those of antelope, kudu and even elephants to strip leaves from the untouched upper reaches of trees. The French zoologist Jean-Baptiste Lamarck is usually credited as the first person to suggest that long necks have evolved in giraffes because they allow them to get to the parts other herbivores cannot reach.

As the giraffe lives "in places where the soil is nearly always arid and barren, it is obliged to browse on the leaves of trees and to make constant efforts to reach them," he wrote in his 1809 book ‘Philosophie Zoologique’. "From this habit long maintained in all its race, it has resulted that the animal's fore-legs have become longer than its hind legs, and that its neck is lengthened."

The English naturalist Charles Darwin also thought the giraffe's extraordinary legs and neck must have something to do with foraging. "The giraffe, by its lofty stature, much elongated neck, fore-legs, head and tongue, has its whole frame beautifully adapted for browsing on the higher branches of trees," he wrote in ‘On the Origin of Species’ in 1859. In short, giraffes' long necks are the result of generation upon generation of repeated stretching and inheritance.

During the dry season when feeding competition should be most intense giraffe generally feed from low shrubs, not tall trees. What's more, giraffes feed most often and faster with their necks bent

Male giraffes often fight for access to females, a ritual referred to as "necking". The rivals stand flank to flank, then start to whack each other with their heads. The top or back of the well-armoured skull is used as a club to strike the neck, chest, ribs, or legs of the opponent with a force capable of knocking a competitor off balance or unconscious. The largest males usually win these battles and do most of the breeding, says zoologist Anne Innis Dagg of the University of Waterloo in Ontario, Canada, who has been studying giraffes since the 1950s. "The other giraffes don't get much breeding opportunity." There is also evidence that females are more receptive to advances from larger males.

Q:

How does a giraffe knock its opponent off balance or unconscious?

• 1
  By pulling the legs of the opponent
• 2
  By using its head as a club and hitting the opponent
• 3
  By biting the opponent’s neck, chest and ribs
• 4
  By entangling its neck in the opponent’s neck