Answer:
Option A, enables an organism to survive and reproduce
Step-by-step explanation:
Adaptation is the mechanism through which an organism become enabled to survive and reproduce in certain environmental condition.
For example - in older days "coil mosquito repellents" were used to kill the mosquitoes but eventually the mosquitoes have evolved and became resistant to the deadly effects of "coil mosquito repellent" . This resistance is a form of adaptation to the existing environmental condition. Thus, from here it is also clear that a species or organism adapts to a changing situation though natural selection process in order to become the "fittest for survival".
Therefore option A, is correct.