Facebook CEO Mark Zuckerberg plans to use a congressional hearing Wednesday on the subject of tech monopolies to defend how big his social media company has become.

Zuckerberg will tell a House Judiciary subcommittee that the popular apps Instagram and WhatsApp are better off under the corporate umbrella of Facebook, despite calls for the government to break up the social giant, according to a copy of Zuckerberg’s prepared testimony released by the company on the eve of the hearing.

“Facebook has made Instagram and WhatsApp successful as part of our family of apps,” Zuckerberg said in the prepared testimony.

“Instagram and WhatsApp have been able to grow and operate their services using Facebook’s bespoke, lower-cost infrastructure and tackle spam and harmful content with Facebook’s integrity teams and technology.”

The topic of Instagram and WhatsApp is important because analysts and lawmakers including Sen. Elizabeth Warren, D-Mass., have called for Facebook to be required to sell off those apps. They have asked whether it’s a good idea for three of the most popular apps in the world for social media and communication to be owned by the same corporation.

Zuckerberg is one of four major tech CEOs scheduled to testify on Wednesday before a House antitrust subcommittee that is examining their power in the marketplace. Chairman David Cilline, D-R.I., has been investigating the tech industry for more than a year and is preparing a report on possible anti-competitive practices.

In prepared testimony of his own for the hearing, Amazon CEO Jeff Bezos defended his company’s practices including its wages and benefits and said that, in business, a large size is sometimes necessary.

“I love garage entrepreneurs — I was one. But, just like the world needs small companies, it also needs large ones," Bezos said. “There are things small companies simply can’t do. I don’t care how good an entrepreneur you are, you’re not going to build an all-fiber Boeing 787 in your garage.”

Bezos said that Amazon now directly employs 1 million people.

In his prepared remarks, Apple’s Tim Cook said his company remains in fierce competition for the smartphone market, noting, “Apple does not have a dominant market share in any market where we do business,” according to comments shared by the committee.

Google CEO Sundar Pichai portrayed his company as offering a competitive platform that has lowered prices for advertisers and offers increased choice for consumers, according to his prepared remarks.

“Competition in ads — from Twitter, Instagram, Comcast and others — has helped lower online advertising costs by 40 percent over the last 10 years, with these saving passed down to consumers through lower prices,” Pichai said.