阅读下面短文，从A、B、C、D四个选项中选出最佳选项。
If you were to walk up Arthur Bonner and say, "Hey, Butterfly Man." his face would break into a smile. The title suits him and he loves it.
Arthur Bonner works with the Palos Verdes blues butterfly, once thought to have died out. Today the butterfly is coming back—thanks to him. However, years ago if you'd told him this was what he'd he doing someday, he would have laughed, "You're crazy." As a boy, he used to be "a little tough buy on the streets". At the age of thirteen, he was caught by police for stealing. At eighteen, he landed in prison for shooting a man.
"I knew it had hurt my mom," Bonner said after he got out of prison. "So I told myself I would not put my mom through that pain again."
One day he met Professor Mattoni, who was working to rebuild the habitat for an endangered butterfly called EI Segundo blue. He saw the sign "Butterfly Habitat" and asked, "How can you have a habitat when the butterflies can just fly away?" Dr. Mattoni laughed and landed him a magnifying glass, "Look at the leaves. I could see all these caterpillars on the plant." Dr. Mattoni explained, " Without the plant, there are no butterflies."
Weeks later, Bonner received a call from Dr. Mattoni, who told him there was a butterfly that needed help. That was how he met the Palos Verdes blue. Since then he's been working for four years to help bring the butterfly back. He grows astragalus, the only plant the butterfly eats. He collects butterflies and bring them into a lab to lay eggs. Then he puts new butterflies into the habitat.
The butterfly's population, once almost zero, is now up to 900. For their work, Bonner and Dr. Mattoni received lots of awards. But for Bonner, he earned something more: he turned his life around.
For six years now Bonner has kept his promise to stay out of prison. While he's bringing back the Palos Verdes blue, the butterfly has helped bring him back, too.
