B) fashions in general that look horrible. Some look good, some don't, girls worry more about what's in and ignore whether it looks good.
C) because of the above, they buy massive amounts of garbage clothing.
D) (men do this too) wearing clothes that don't fit because they are unhappy with their shape. For women, it can be either squeezing into clothes too small or going the other way and wearing super loose clothes to 'hide' in or so it doesn't look tight. Everyone looks best in clothes that fit well. If your clothes fit you, you fit the clothes - so YOU look the right size.