Paring synonyms here can be tricky, so I'll start with the sentence. We have two idea chuncks that are connected by the logic word "and" this means that they are supporting each other. In the left side of "and" it states that the discovery was a turning point (which is a good thing), meaning that the blank must be a good thing as well to follow the logic of the sentence. Knowing this I can cross out dampened, abetted and debilitated; leaving me with motivated, vitalized and stimulated. I am going to guess motivated and stimulated since they are more closely related, vitalize is to give energy (it could be a trap answer).

If I am wrong please let me know