The Magoosh GRE Diagnostic Quizzes are a way for new students to test their knowledge and determine which study plans will work best for them. Once you take each GRE Diagnostic Quiz, you will receive an email with the answers and text explanations.
You can also find the key with links to video explanations here: GRE Diagnostic Quiz Answer Key. You will need a Premium Magoosh account to access many of the answer explanations.
Premium students can send questions about the diagnostic quizzes to firstname.lastname@example.org :D