A、She was a farmer. B、She was a cow. C、She was a rescuer. D、She was a horse. B文中提到Lizzie, one of her oldest and favorite cows，由此

Six consecutive days of spring rain had created a raging river running by Nancy Brown’s farm. As She tried to herd her cows to higher ground, she slipped and hit her head on a fallen tree think. The fall knocked her out for a moment or two. When she came to, (32) Lizzie, one of her oldest and favorite cows, was licking her face. The water was rising. Nancy got up and began walking slowly with Lizzie. The water was now waist high. It was quite hard to walk in the water. Nancy’s pace got slower and slower. Finally, all she could do was to throw her arm around Lizzie’s neck and try to hang on. About twenty minutes later, Lizzie managed to successfully pull herself and Nancy out of the raging water and onto a bit of high land, a small island now in the middle of acres of white water.
    Even though it was about noon, the sky was so dark and the rain and lightning so bad that it took rescuers another two hours to discover Nancy. A helicopter lowered a paramedic, who attached Nancy to a life-support hoist. (33) They raised her into the helicopter and took her to the school gym, where the Red Cross had set up an emergency shelter.
    When the flood finally subsided two days later, Nancy immediately went back to the "island". (34) To her great grief, Lizzie was gone. She was one of nineteen cows that Nancy lost. "I owe my life to her," said Nancy sobbingly.