Mark the option that could replace the idiom in the sentenc...

        Miss Lucy was the only guardian present. She was leaning over the rail at the front, peering into the rain like she was trying to see right across the playing field. I was watching her as carefully as ever in those days, and even as I was laughing at Laura, I was stealing glances at Miss Lucy’s back. I remember wondering if there wasn’t something a bit odd about her posture, the way her head was bent down just a little too far so she looked like a crouching animal waiting to pounce. And the way she was leaning forward over the rail meant drops from the overhanging gutter were only just missing her – but she seemed to show no sign of caring. I remember actually convincing myself there was nothing unusual in all this – that she was simply anxious for the rain to stop – and turning my attention back to what Laura was saying. Then a few minutes later, when I’d forgotten all about Miss Lucy and was laughing my head off at something, I suddenly realised things had gone quiet around us, and that Miss Lucy was speaking.

(Excerpt from Never Let Me Go, by Kazuo Ishiguro. Available on https://www.nobelprize.org/prizes/literature/2017/ishiguro/prose/)