In the following question on idioms, choose the alternative which best expresses the meaning of the phrase "To put a spoke in one's wheel".

Introduction / Context:
Idioms are fixed expressions whose meanings cannot be guessed only from the individual words. The phrase to put a spoke in one's wheel is derived from an old image of interfering with the motion of a wheel by interfering with its spokes. In modern English, this idiom describes actions that obstruct or hinder another person's progress or plans, often deliberately.

Given Data / Assumptions:

• Idiom: To put a spoke in one's wheel.
• Options: To be advantageous at the time of difficulty, To maintain under all circumstances, To blame the other party, To put a difficulty in the way of progress, and To encourage someone to move faster.
• The mental picture is of inserting an object into a wheel so that it cannot turn smoothly.
• The correct explanation should reflect obstruction rather than help.

Concept / Approach:
Literally, the spokes are the bars that connect the hub and the rim of a wheel. If someone puts a spoke or some foreign object in the wheel, the wheel may jam or break, stopping movement. Figuratively, the idiom means to create obstacles or problems in someone else's plans, delaying or preventing their progress. Therefore, the best paraphrase among the options is to put a difficulty in the way of progress. The other choices describe helping, maintaining, blaming or encouraging, which do not match the core idea of deliberate obstruction.

Step-by-Step Solution:
Step 1: Visualise the literal action of interfering with a wheel's movement by putting something in its spokes.
Step 2: Translate that image to a social or professional context where one person obstructs another person's plans.
Step 3: Compare each option with this concept of creating obstacles.
Step 4: Identify To put a difficulty in the way of progress as the only option that directly expresses hindrance.
Step 5: Reject options that suggest helpfulness, maintenance, blame or encouragement.

Verification / Alternative check:
Example sentences clarify usage: Every time we try to improve the system, someone in the department puts a spoke in our wheel. Here it is clear that the person is not helping but obstructing. Rewriting this with To put a difficulty in the way of progress gives the same meaning. Replacing it with To blame the other party or To be advantageous at the time of difficulty would not make sense in this context. Similarly, using To encourage someone to move faster would be the opposite of what the idiom conveys. This confirms that the correct meaning is about obstruction.

Why Other Options Are Wrong:
Option A, To be advantageous at the time of difficulty, suggests helping or benefiting someone in tough times, which is opposite to putting obstacles in their path. Option B, To maintain under all circumstances, relates to keeping something going, again the opposite of obstructing it. Option C, To blame the other party, focuses on assigning fault, not on creating difficulty in their progress. Option E, To encourage someone to move faster, describes support and motivation, not hindrance. Only option D matches the literal and figurative core of the idiom.

Common Pitfalls:
Students sometimes misinterpret idioms because they translate them word by word into their own language or guess from one component only. For to put a spoke in one's wheel, focusing on spoke alone may not help; it is the entire image of interfering with the wheel that gives the clue. A practical strategy is to learn idioms with short example sentences so that their meaning is connected to context rather than to isolated words.

Final Answer:
The idiom To put a spoke in one's wheel means to put a difficulty in the way of progress.