The crossword clue “Thesis defense, e.g.” had me scratching my head for a moment, but using my powers of deduction and wordplay, the answer became clear. “Thesis defense” immediately led me to think of a university setting, where students defend their theses in front of a panel of professors. But what type of exam is this? I considered “written exam” but quickly dismissed it, as a thesis defense usually involves more than just written work. Then, “oral exam” popped into my head as a possibility. “Oral” refers to spoken language or speech, which would make sense for defending a thesis in front of a panel. But wait, “oral” alone is not enough letters for the crossword solution. Aha! The word “exam” fit perfectly at the end, making ORAL EXAM the answer. It all clicked – an oral exam is a type of test where a student defends their thesis orally. Mystery solved!