Peeta Mellark: Your favorite color is green. Real or not real?
Katniss Everdeen: Real. Your favorite color is orange; Not a bright orange, but a soft orange, like the sunset.
Peeta Mellark: Thank you.
Peeta Mellark: You love me. Real or not real?
Katniss Everdeen: Real.
Katniss Everdeen: You should have been the Mockingjay.
Johanna Mason: True. But no one likes me.
Katniss Everdeen: They trusted you to get people out.
Johanna Mason: We had adjacent cells in the Capitol. We're very familiar with each other's screams.
Katniss Everdeen: We all have one enemy, and that's President Snow! He corrupts everyone and everything! He turns the best of us against each other... Stop killing for him! Tonight, turn your weapons to the Capitol! Turn your weapons to Snow.
Katniss Everdeen: Stay with me.
Peeta Mellark: Always.
Peeta Mellark: Our lives were never ours, they belong to Snow, and our deaths do too. But if you kill him, Katniss, all those deaths, they mean something.
Answer: Coin was ultimately responsible. Coin sent Prim to the Capitol and then had the Capitol bombed. The rebels, led by Coin, used hovercrafts with the Capitol insignia on it to drop the bombs so that the public thought it was the Capitol bombing their children. Coin wanted Katniss to blame Snow for Prim's death to get her full support.
Bishop73