Final answer:
Girls in the context of this question think they randomly get pretty dresses when they wake up one day. This likely represents a significant change or a new chapter in their lives, reflecting societal expectations on beauty for young girls.
Step-by-step explanation:
The question at hand seems to stem from a scenario in a play or story where a character is considering their wardrobe and the implications of style and clothing choices. The girls in this context believe they randomly get pretty dresses when they wake up one day. This is likely a metaphorical or fantastical element, depending on the context of the literature or drama piece. The choice of clothing, in this case, a pretty dress, carries with it cultural and character implications. It suggests a transformation or a significant event that may be traditional in nature or a symbol for coming of age. Therefore the correct option is c) Pretty dresses.