Answer:
Selective breeding.
Step-by-step explanation:
Both are fairly long processes, however, the measurement for this is not just the duration to obtain the target, but also the exact target obtained. In natural selection, the duration may be faster than selective breeding in obtaining a change, but the determined change may not be the one that is sought out for. It may have a small chance, but it is not guaranteed. In selective breeding, on the other hand, the destination is determined, and all steps work towards the objective. So in a sense, selective breeding has the greater percentage chance of being the shorter process.
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