hi! a figure of speech is a phrase used in a non-literal sense, with a meaning behind it. knowing this, we can try to find which one is a figure of speech!
you can generally tell what each sentence means. both b, c, and d say it in a literal sense and get to the point. for example, d mentions that the falling snow made them struggle to see in the dim light.
so, A is the figure of speech! it says, the snowflakes danced across the lawn, not sticking or accumulating at all. you can guess, that the snowflakes very obviously did not dance!
hope this helped!:)