The key answer of exercise 2
The key to exercise solutions in chapter 6.2 - Grammar for the textbook Wider World 4 - Student's Book with authors Suzanne Gaynor, Kathryn Alevizos and Carolyn Barraclough from Pearson Education
Question
Look at the photo in the text. What sort of test do you think this is?
Answer
It's a test for colour-blindness.