Her stock is up.

Adena Friedman has quite the resume. The NASDAQ chief exec and president was the first woman ever to be named the CEO of a major U.S. stock exchange operator, a job she does while also maintaining a black belt in karate and raising a family.

One of the things she says helped propel her to where she is: attending an all-girl’s school. Speaking on CNBC’s “Life Hack’s Live” this week, Friedman says that her 10 years at a single-sex school “made a difference” helping her learn to speak her mind and pursue her passions.

“While I had a brother at home, I was able to go to a place where I could feel that I could ask any question I wanted,” said Friedman. “I could feel that it was OK to be smart, honestly, that I really loved math and science, and that I was really able to propel myself into those fields and not really have any of those sort of social pressures that sometimes co-ed environments can create.”

When Friedman went off to a co-ed college (she graduated from Vanderbilt University) she saw that women didn’t ask as men questions as much as men in class. “But I always asked a lot of questions — so I do think it [going to all all-girl’s school] actually helped me create a sense of confidence and realizing that I could be as strong and as smart as anyone else in the room,” she says.

Friedman may be onto something: Some research shows that going to an all-girl’s school benefits women. For example, a study from 2009 found that it increased women’s confidence in math and computer science; women who attended these schools also had higher average SAT scores.

But other research, including this meta-analysis of 184 studies on the topic, finds that there aren’t benefits. Hence the debate on the topic, which led the National Education Association to simply conclude: “We all can agree that we need to construct an educational environment that meets the social and intellectual needs of boys and girls.”