Explanation:

This question asks us to identify the option where the given single word (एक शब्द) is *not* suitable for the provided phrase (वाक्यांश). This tests our knowledge of 'अनेकार्थी शब्द' (one-word substitutions) in Hindi, which are often derived from Sanskrit roots and convey specific desires or states. Let's analyze each option: **Option (A): युद्ध करने की प्रबल इच्छा – युयुत्सा (Yuyutsa - strong desire to fight)** 'युयुत्सा' (yuyutsā) correctly means 'the strong desire to fight' or 'belligerence'. It is derived from the root 'युध्' (yudh, to fight). This pairing is accurate and suitable. Therefore, this option is correct. **Option (B): जीने की तीव्र इच्छा - जिजीविषा (Jijivisha - intense desire to live)** 'जिजीविषा' (jijīviṣā) correctly means 'the intense desire to live' or 'will to live'. It is derived from the root 'जीव्' (jīv, to live). This pairing is accurate and suitable. Therefore, this option is correct. **Option (C): मोक्ष प्राप्ति की इच्छा – मुमूर्षा (Mumursha - desire for salvation/liberation)** This option presents a mismatch. 'मोक्ष प्राप्ति की इच्छा' means 'the desire for salvation' or 'the desire for liberation'. The correct single word for this desire is 'मुमुक्षा' (mumukṣā), derived from the root 'मुच्' (muc, to free, to liberate). However, the word provided is 'मुमूर्षा' (mumūrṣā). 'मुमूर्षा' actually means 'the desire to die' or 'the desire for death', derived from the root 'मृ' (mṛ, to die). Since 'desire for salvation' and 'desire to die' are distinct and opposite concepts, 'मुमूर्षा' is *not* suitable for the phrase 'मोक्ष प्राप्ति की इच्छा'. This pairing is incorrect. **Option (D): जीतने की इच्छा – जिगीषा (Jigisha - desire to win)** 'जिगीषा' (jigīṣā) correctly means 'the desire to win' or 'the desire for victory'. It is derived from the root 'जि' (ji, to conquer, to win). This pairing is accurate and suitable. Therefore, this option is correct. **Conclusion:** Based on the precise meanings of the one-word substitutions, option (C) is the one where the given word ('मुमूर्षा') is not suitable for the phrase ('मोक्ष प्राप्ति की इच्छा'). The correct word for 'desire for salvation' is 'मुमुक्षा'. Therefore, option (C) is the correct answer.