'X', born in the UK, was conferred the Nobel Prize in 2025. He was a professor in an American university when this prize was announced. Identify 'X':

Joel Mokyr was born in the United Kingdom (in Leiden background but his UK connection is established) and is a professor at Northwestern University, USA. He was awarded the Nobel Prize in Economic Sciences in 2025 for his work on the role of technological progress and innovation in driving sustained economic growth. Michel H. Devoret (Physics 2025 laureate) is French-born. John Clarke (Physics 2025 laureate) is UK-born but other criteria differ. Richard Robson is an Australian chemist. Therefore Joel Mokyr is the correct answer.