Sure, let's go through each set of words to identify the one whose underlined part is pronounced differently from the others:

1. A. normal
2. A. basic
3. A. ceremony
4. A. country
5. A. camel
6. A. entertain
7. A. traffic
8. A. apartment
9. A. create
10. A. accessible

Here are the answers:

1. **D. chore** - The "o" in "chore" is pronounced differently from the "o" in "normal," "major," and "transport."
2. **B. visitors** - The "i" in "visitors" is pronounced differently from the "a" in "basic," "major," and "craft."
3. **D. costume** - The "o" in "costume" is pronounced differently from the "e" in "ceremony," "cultural," and "craft."
4. **D. mouse** - The "ou" in "mouse" is pronounced differently from the "ou" in "country," "cloud," and "cattle."
5. **D. buffalo** - The "a" in "buffalo" is pronounced differently from the "a" in "camel," "cattle," and "paddy."
6. **C. air** - The "ai" in "air" is pronounced differently from the "e" in "entertain," "rain," and "strain."
7. **D. jam** - The "a" in "jam" is pronounced differently from the "a" in "traffic," "relative," and "tragedy."
8. **B. offer** - The "o" in "offer" is pronounced differently from the "a" in "apartment," "prefer," and "another."
9. **D. easily** - The "ea" in "easily" is pronounced differently from the "ea" in "create," "peaceful," and "increase."
10. **D. success** - The "u" in "success" is pronounced differently from the "a" in "accessible," "pressure," and "illness."