Three examiners suspended amid claims that teachers were being secretly advised how to boost GCSE and A-level results will give evidence to Parliament today.
The trio were suspended after it was alleged to undercover reporters that teachers were given unfair advice about forthcoming exams.
It was also claimed that one exam board set easier tests than others.
The Daily Telegraph released video footage of a chief examiner at Edexcel who claimed the company's GCSE geography tests were not as difficult as those from other exam boards.
Steph Warren also described her disbelief that the test had been cleared by Ofqual - the regulator of qualifications, examinations and assessments.
Speaking at an Edexcel seminar in Birmingham last month, she said teachers should choose their exam because "you don't have to teach a lot".
A spokesman for Edexcel said Ms Warren had been suspended pending an investigation into her comments and allegations regarding disclosure of future exam content.
Two examiners with WJEC - the Welsh exam board - were suspended following claims which centred on teachers being given detailed advice on forthcoming exam questions and how students could score higher marks.
It is understood the examiners are Paul Evans and Paul Barnes, both of whom were named in the Telegraph's report.
The three are due to give evidence at 9.30am to the Education Committee's inquiry into the administration of examinations for 15 to 19-year-olds in England.
The committee, chaired by Conservative MP Graham Stuart, will also hear from various examination board bosses and Glenys Stacey, Ofqual chief executive, and Dennis Opposs, the regulator's director of standards.