(CNN) — White House press secretary Sarah Sanders faced questions Thursday for the second day in the row about President Donald Trump’s mental fitness to serve as president.

US President Donald Trump in Washington, DC on December 18, 2017.
(credit: MANDEL NGAN/AFP/Getty Images)

“It’s disgraceful and laughable. If he was unfit, he probably wouldn’t be sitting there, wouldn’t have defeated the most qualified group of candidates the Republican Party has ever seen,” Sanders said, before praising Trump as an “incredibly strong” leader.

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White House press secretary Sarah Sanders (CNN)

The questions come in the wake of the chaotic picture painted of the President in Michael Wolff’s “Fire and Fury: Inside the Trump White House.”

CNN has not independently verified all the details in Wolff’s book.

Sanders disparaged the book, calling it “complete fantasy” and characterizing it as “sad” and “pathetic.”

When asked about examples of falsehoods, Sanders said she couldn’t go through every page but pointed specifically to the claim that Trump didn’t know who former House Speaker John Boehner was.

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Sanders called the book “complete fantasy and “full of tabloid gossip.”

She also claimed that basic information is wrong, pointing to ages of employees, which Sanders said would have been “super easy to check.”

On Wednesday, Sanders said Americans should be more concerned about Kim Jong Un.

“I think the people of this country should be concerned about the mental fitness of the leader of North Korea. He’s made repeated threats. He’s tested missiles time and time again for years, and this is a president who is not going cower down and is not going to be weak and is going to make sure he does what he’s promised to do, and that’s stand up and protect the American people,” Sanders said during the White House press briefing.

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