In the following question on English idioms, choose the alternative which best expresses the meaning of the expression At loose ends, often used to describe an unsettled or uncertain state.

Introduction / Context:
This idiom question focuses on the expression At loose ends. The phrase is often used to describe a person who does not know what to do next, feels unsettled, or has uncompleted tasks. It appears in both spoken and written English to mark periods of uncertainty, unemployment, or transition when someone lacks clear direction or occupation.

Given Data / Assumptions:

• Idiom given: At loose ends.
• Options describe tying thread, keeping options open, being in uncertainty, and repaying debts.
• You must choose the option capturing the sense of not being settled or properly engaged.
• The expression refers to a mental or situational state, not a physical action with thread.

Concept / Approach:
At loose ends is an idiom that suggests a lack of clear duties, plans, or emotional stability. A person at loose ends may feel restless, bored, or unsure of what to do next. The best option will express this idea of uncertainty or lack of structure in life or work. It does not literally refer to sewing, nor does it mean deliberately keeping future choices open or making payments.

Step-by-Step Solution:
Step 1: Recall that at loose ends usually describes someone who is idle, confused, or unsure about their next move. Step 2: Examine option a, tie two loose ends of a thread, which is a physical action and not an idiomatic meaning. Step 3: Examine option b, keep options open. This indicates a strategic decision, often positive, and does not capture the feeling of restlessness or confusion. Step 4: Examine option c, in an uncertain situation. This reflects a state of not being sure what to do or how things will turn out. Step 5: Examine option d, repay debts, which concerns finances and does not relate to the idea of being unsettled. Step 6: Decide that option c best represents the idiomatic meaning of at loose ends.

Verification / Alternative check:
Consider a sentence such as After losing his job, he was at loose ends for several months. Clearly, the sentence describes a period when he was unsure about his next step, not a time when he was happily keeping options open by choice. If we replace at loose ends with in an uncertain situation, the meaning remains very similar. On the other hand, replacing it with repay debts or tie loose ends would not fit the context. This confirms that option c is most accurate.

Why Other Options Are Wrong:
Tie two loose ends of a thread: Literal action that belongs to sewing, not to emotional or career situations.
Keep options open: Implies a conscious strategy for flexibility, rather than the discomfort of not knowing what to do.
Repay debts: Refers to financial transactions and has no connection to the idiom in question.

Common Pitfalls:
Learners sometimes confuse at loose ends with tie up loose ends, another idiom that means to complete remaining small tasks. At loose ends is about feeling adrift, while tie up loose ends is about finishing work. Keeping these expressions separate in your mind and noticing the different prepositions will help prevent errors. Regular exposure to natural English texts such as novels and biographies will show you these idioms used in context and reinforce the correct meanings.

Final Answer:
The idiom At loose ends means being in an uncertain situation, so option c is correct.