The correct answer is **has been working, is** (Option 2). **Comprehensive Derivation:** The correct answer is 'has been working, is'. Explanation & Key Takeaways: • From the sentence we understand that it is about an activity that started in the past and is still continuing. • Present Perfect Continuous tense is used in such cases. • The general form of Present Perfect Continuous tense is - 'Subject + has/have + been + verb + -ing'. • Therefore, we understand that 'has been working' is the correct answer. • 'is' is used in third-person singular form of 'be'. • Hence, option 2 is the correct answer. Therefore. the correct sentence is -'Keval has been working in this office for the last five years and is a sincere worker'. **Option Elimination:** • **Option 1 (worked, is)**: Incorrect distractor. • **Option 2 (has been working, is)**: Correct Answer; accurate according to canonical reference. • **Option 3 (has worked, is)**: Incorrect distractor. • **Option 4 (working, is)**: Incorrect distractor. **Exam Trap:** Be careful of misleading distractors and subtle terminology differences. Verify core properties before selecting your answer. **Memory Booster:** Core mnemonic rule: has been working, is corresponds to Option (2).