A theme of this story is "overconfidence leads to carelessness." Which excerpt from the text most effectively demonstrates how Giselle's thoughts and actions develop this theme?

A "Slowly Dark Star warmed up to her, and one cold spring afternoon, he approached Giselle and gently nudged her, filling her with euphoria."

B "It had been almost four weeks since she’d ridden Dark Star, and Giselle was adamant that her broken arm would not inhibit her riding."

C "Giselle opened the horse’s stall, and even though it was a bit of a struggle with only one good arm, she managed to bridle him and lay a blanket across his back."

D "Once outside and out of view, Giselle climbed the railings of the corral fence, clambered up on the bay, and wriggled into position on the horse’s back."