💡 Detailed Explanation
The correct answer is 「順調」 (junchō), which means 'smoothly', 'without a hitch', or 'favorably'. It is commonly used in the adverbial form 「順調に」 to describe the progress of an event or task. 「好調」 (kōchō) means 'in good condition/doing well' (e.g., sales, athletes). 「快調」 (kaichō) means 'perfect condition'. 「順位」 (juni) means 'ranking'. Let's ensure choices are unique: ['順調', '好調', '快調', '順位'].