Giraffes use their extremely long necks to reach the leaves high up on acacia trees, which other animals can not reach, giving them a food source for which they have few competitors. What can you conclude about natural selection from this observation?

Question

josedavid · Answer

Giraffe necks get longer over a lifetime of stretching, and their offspring inherit the longer necks of their parents.
 All giraffes are born with short necks and, eating acacia leaves causes them to stretch over a lifetime.
 Other animals will mimic the giraffe and grow longer necks.
 The giraffes with the longest necks survive and produce offspring.

anonymous · Answer

I believe it's the first one, but the last one is still a possible option.