I need an answer for the questions with an explanation

The diageram ropresents the cmission spoctrum of hydrogen. Groups of mrows are labellod W. X and Y. Which statement is correct? A. The arrows represent the transition of electrons to different energy levels when heat is supplied. B. The arrows of W represent emission in the UV region. C. The smallest arrow of X represents a violet line in the emission spectrum. D. The arrows of Y represent emission of electromagnetic waves with higher energy than those represented by X and W