Some of Donald Trump's key allies will face a grilling by senators this week, as part of a tense process that will see them either approved or rejected for the roles the president-elect has nominated them for. The hearings, which begin on Tuesday, are the first chance for senators to publicly quiz some of Trump's more controversial picks. They will then need to be confirmed to their roles by a vote. And while the upper chamber of Congress is now controlled by Trump's Republican Party - just three defections could be enough to deny a nominee a job. Here are some of the difficult questions those nominees are likely preparing to face. Pete Hegseth - defence secretary One of the first confirmation hearings is set to be one of the most closely watched. Trump's nominee for defence secretary is expected to face questions on Tuesday about his lack of management experience, his alleged heavy drinking, as well as his previous opposition to women serving in combat roles in the military. Hegseth could also be asked about an accusation that he sexually assaulted a woman in a California hotel room in 2017. He denies the claim and maintains the encounter was consensual. The allegation was investigated, but Hegseth - a Fox News host and military veteran - was never arrested or charged. Why Trump's defence pick surprised Washington Hegseth and the unnamed accuser then reached a confidential financial settlement in 2023. His lawyer later told the Associated Press that the payment was intended to prevent a baseless lawsuit. Trump has stood by his pick, who is among the nominees who have been busy courting senators in recent days to try and shore up the necessary votes. Kristi Noem - homeland security secretary In the spotlight on Wednesday will be the woman who could be tasked with carrying out one of Trump's top campaign pledges - billed by his team as the largest mass deportation of illegal immigrants in American history. As the president-elect's choice for homeland security secretary, Noem could be quizzed on the logistics of enacting this pledge. A mass deportation programme on the scale proposed would likely face logistical or legal difficulties, experts say. Noem could also face questions on other potential immigration policies, such as Trump's vow to end birthright citizenship. She has been a loyal and vocal backer of the president-elect's pledges, which is consistent with other nominees and appointees for Trump's second term in the White House.