Spoilers for Mass Effect 3
The law of Roberts' Trident dictates that whenever a video game offers a third choice, the third choice is always going to be the best and/or a copout. I coined this term when finishing Mass Effect 3, because the developers didn't want the ~92% Paragon players to go with the logical choice of the Renegade option which would destroy the Reapers, even if it would mean killing the newly liberated Geth (and if you did as I did, it didn't come at the cost of the Quarians). The Paragon version was to take control of the Reapers, to make them move far away. I chose the cop-out, which was Synthesis. This ending allows you to merge artificial and organic life to create an unending (to our knowledge) peace and amass all knowledge in the universe. Evolution had hit its peak. That is logical, but it ignores the emotional and philosophical truth of the matter, which the game doesn't show (they say ignorance is bliss). As Lorerunner once said, imagine if you were a Husk, and were given this newfound sense of life. Imagine tasting the chrome and ash in your mouth, or smelling the heat from the circuitry that made you. Imagine the agony that comes with movement, a sensation you didn't before your senses were robbed by Indoctrination. And what have you achieved, besides doing what Saren Arterius wanted to? The Paragon option is also as disastrous, as we'd stopped The Illusive Man achieving this end also. The fact of the matter is, we've spent three games trying to reach the ending that makes things go red, and I didn't do that.
Spoilers for Mass Effect 3 End
That's not really a decision though, unless we count not playing the game we've put 40 big ones down on is a choice. There's other choices in The Line that exist, which put you between a rock and a hard place, but they're not quite as remarkable as that moment.