Choose the world whose underlined part differs from the other three in pronunciation in the following question

Ex1: Choose the world whose underlined part differs from the other three in pronunciation in the following question.
1. A. tidy       B. pollution     C. protect     D. prevent 
2. A. plastic     B. pollute       C. waste      D. picture 
3. A. plant         B. water       C. section       D. forest 
4. A. caused       B. affected      C. provided   D. prevented 
5. A. protect        B. water         C. national         D. plastic