After marriage, Mrs. Karanja ran a store with her friends.

　　定位到文中第一段的第四句，"After marriage, she and her husband ran a hardware store（五金店）for seven years, but then she wanted to do something more interesting."，结婚之后，她和他的丈夫一起经营了一家五金店长七年时间，但之后她想做一些更感兴趣的事情。由此可知，Mrs. Karanja结婚之后是与她丈夫一起经营的商店，而不是和她的朋友，题目与原文意思不相符，故选B。