CNBC.com's Pippa Stevens brings you the day's top business news headlines. On today's show: a recap of the four-hour hearing on Capitol Hill on the jaw-dropping GameStop short squeeze engineered by retail traders in January. Plus, CNBC.com's Jacob Pramuk explains the debate in the Democratic party over student debt forgiveness.

Citadel's Ken Griffin defends controversial Wall Street practice, says firm would adapt if it were outlawed

During Thursday's GameStop hearing, Citadel Securities' Ken Griffin defended a controversial method brokerages use to make money, and said his firm would adapt if new regulations prohibited the practice.

Lawmakers finally got a chance to press Robinhood, Citadel and Reddit chiefs about the GameStop trading controversy.

Members of Congress spent much of their time prodding about "payment for order flow," a practice in which a brokerage receives payment from a market maker, known as a dealer, for directing the order to them.

This model is how Robinhood and other brokers are able to have commission-free trading.

Students lament Biden refusal to cancel $50,000 in student debt

President Joe Biden has essentially ruled out canceling $50,000 in student debt per person — disappointing some student borrowers who were counting on that help.

"I didn't have my hopes up," said Joshira Maduro, 30.

The research analyst graduated from Lehigh University in 2012 with a bachelor's degree in finance and marketing and a student loan tab of $132,000. She has been on a strict budget in order to afford her monthly payments ever since.

The payment pause on federal student debt during the coronavirus pandemic has offered Maduro, who lives in Charlotte, North Carolina, a rare opportunity to chip away at the balance of her highest-interest loans and even start building an emergency savings fund.

Meanwhile, the president's proposal to forgive up to $10,000 in student debt per borrower, which is still on the table, would go a long way toward achieving even greater financial milestones, Maduro said, such as buying a car or saving for the down payment on a house.

Treasury Secretary Janet Yellen makes push for major stimulus, sees bigger risk in not doing enough

Treasury Secretary Janet Yellen on Thursday said a large stimulus package is still necessary to get the economy back to full strength, despite momentum suggesting that growth is off to a faster start than anticipated in 2021.

In a CNBC interview, the lead economic official in the Biden administration said the $1.9 trillion proposal could help the U.S. get back to full employment in a year.

"We think it's very important to have a big package [that] addresses the pain this has caused – 15 million Americans behind on their rent, 24 million adults and 12 million children who don't have enough to eat, small businesses failing," Yellen told Sara Eisen on "Closing Bell."

"I think the price of doing too little is much higher than the price of doing something big. We think that the benefits will far outweigh the costs in the longer run," she added.