As far as I am aware, verglas means "black ice", not just "ice". The hints even say so, but none of the exercises including "verglas" currently accept "black ice" as an answer. Reported.
Yes, that is what it means, but when referring to icy road conditions, one generally says just "ice". And "black ice" is accepted in all variations of this sentence.
I put "it is icy". It should be accepted