Here are the words with their underlined parts pronounced differently from the others:

I.
1. **a. exciting** (the "c" in exciting is pronounced /ɪk/)
2. **a. memorable** (the "o" in memorable is pronounced /ə/)
3. **a. course** (the "ou" in course is pronounced /ɔː/)
4. **a. grilled** (the "g" in grilled is pronounced /g/)
5. **b. software** (the "ft" in software has a different sound compared to the others)

II.
1. **a. definitely** (the stress is on the first syllable, while others are on the second syllable)
2. **b. along** (the stress is on the second syllable, while others have stress on the first)
3. **a. scenery** (the stress is on the first syllable, while the others have stress on a different syllable)
4. **b. touching** (the stress is on the first syllable, while the others have stress on a different syllable)
5. **c. specialty** (the stress placement is different compared to the others)

For a further breakdown or clarification, let me know!