The words that need correction are:

1. **A. When** - should be corrected to **B. me**.
2. **C. am leading** - should be corrected to **D. visitors**.
3. **A. is** - should be corrected to **B. with**.
4. **D. pay a visit** - should be corrected to **C. time**.
5. **A. is aware** - is correct.
6. **B. protection** - is correct.
7. **C. heritage** - is correct.
8. **D. better** - should be corrected to **D. better**.

Overall:

- For sentence 1: Change **B. me**
- For sentence 2: Change **C. am leading**
- For sentence 3: Change **A. is**
- For sentence 4: Change **C. time**

Thus, the corrections needed are **B, C, A, C.**