Rearrange the following sentences to form a coherent paragraph:
1. This process, a cornerstone of evolution, ensures that only individuals best suited to their environment survive to reproduce. 2. The diversity of life on Earth is the result of a gradual process of change over vast spans of time. 3. This leads to the gradual accumulation of favorable traits within a population. 4. It begins with inherited variation among individuals, where some possess characteristics that give them an advantage over others.
A2, 1, 4, 3
B4, 3, 1, 2
C2, 4, 3, 1
D1, 2, 4, 3
