Ответ:

C

1. It's becoming more and more difficult ___
2. the textbook just gets more and more complicated
3. I spend more and more time on work
4. my list of things to do gets longer and longer.
5. My problems are just getting worse and worse

D

1. The earlier you leave, the quieter the roads are
2. The bigger a supermarket is , the wider the choice is
3. The more I try to work this out, the more confused I get
4. The more you practice, the more fluently you can speak
5. The better the weather is , the crowder the beaches get