"Listen, we don't have a lot of time. They told me that only one of us was going to make it, and that they were going to let our friends choose."
Rachel Dawes to Harvey Dent, from The Dark Knight
"Don't worry, I'm going to tell you where they are, both of them. And thats the point. You'll have to choose."
"Which of my friends do I condemn to death?"
—Captain Kirk from the Star Trek series, during The Immunity Syndrome (S02E18) in particular.
Here is your final test. Take this gun... And shoot one of these two people! Your beloved girfriend Sheila or your beloved dog, Salty
—Some evil person, this Nedroid strip.
"So...? Which of you instigated it? Hatsuharu? You? Whch of you will incur my displeasure? You see, when I get mad, I can't really see what's around me. Hatori's left eye - that was unfortunate."
—Akito, from Fruits Basket

Optimus: "Give up the Allspark, or give up the Earth. How am I supposed to decide?"

Ratchet: "Heroes are the ones who make the hard choices."
"A weighty choice is yours to make: / The right selection or a big mistake. / If the wrong choice you choose to pursue, / the foundations of home will crumble without you."

(Quackerjack, Louie and Dewey are near the gondola system.)
Quackerjack: Behold! My master plan! On one gondola, dozens of innocent citizens. On the other, convicted criminals. And both gondolas are filled with high explosives. Hehehehe!
Dewey: So?
Quackerjack: So, I gave the people on each gondola a detonator for the other. Now, each side is faced with a moral dilemma. Kill or be killed, and they have 15 minutes to decide before I do! Hahaha!
(A gondola blows up.)
Quackerjack: What the...?! What just happened?!
Louie: Looks like the criminals blew up the civilians.
Quackerjack: But they weren't supposed to do that! I wanted to push the button!
Dewey: Then you shouldn't have given them detonators.

Louie: Especially to the criminals.