I'm preparing an answer key for my students and my document looks like this:
Q1:XXXXXXXX?
1. XXX
2. XXX
3. XXX
4. XXX
2 (option 2. is the correct answer to the 1st question)
(a blank line)
Q2:XXX?
...(repeat)

Is that possible to write a macro to color the respective correct options into red based on the key provided on every 7th line and then delete all those lines? Does anyone have a hint?