Here are the answers based on the provided questions:

1. **Question 1:** C (books) - is the odd one out as it is a type of item, while the others can be related to items used for writing or measuring.

2. **Question 2:** A (play) - is the correct choice as it is not an activity associated with studying compared to the other options.

3. **Question 3:** B (playing) - is the right answer since it describes an action in the present continuous form, while the others imply different states or levels.

4. **Question 4:** B (country) - is the word that is closest in meaning to "the area east of the river."

5. **Question 5:** D (amused) - is opposite to "delighted," as it indicates a lack of enjoyment.

Please adjust as necessary based on your specific needs or the context of the questions.