What does the underlined sentence “she is at a loss to explain it” mean?
选项：

A:In her opinion it was a loss to the clothes shops where she stole things.
B:She doesn’t have any idea why she has the desire to steal from shops.
C:She thinks it is a loss for her to explain why she stole things from shops
D:Personally she feels ashamed and embarrassed for her shoplifting actions