In the following question on English idioms, choose the alternative which best expresses the meaning of the expression With might and main, used to describe putting in maximum effort.

Introduction / Context:
This idiom question explores the expression With might and main. The phrase is somewhat old fashioned but still appears in literature, speeches, and examination passages. It combines two words for strength, might and main, to emphasise the idea of using all available energy or power to do something.

Given Data / Assumptions:

• Idiom: With might and main.
• Options speak about risk, force, confidence, and blessings.
• You must select the option that conveys the sense of maximum physical or mental effort.
• The phrase refers to strength and exertion, not to luck, faith, or risk taking.

Concept / Approach:
With might and main means with all ones strength, with great force, or with full effort. The correct alternative should therefore focus on the intensity of effort, not on emotional states like confidence or external factors like blessings. Among the options, with full force matches this meaning most closely, as it expresses the idea of putting all energy and power into an action.

Step-by-Step Solution:
Step 1: Recall that might is another word for strength or power, and main historically also referred to strength. Step 2: Understand that combining might and main intensifies the sense of effort. Step 3: Examine option a, with full risks, which focuses on danger rather than strength. Step 4: Examine option b, with full force, which clearly relates to using maximum power or energy. Step 5: Examine option c, having full confidence, which relates to belief in success, not necessarily to the level of exertion. Step 6: Examine option d, with full blessings, which suggests spiritual support, not physical or mental power. Step 7: Conclude that option b best expresses the idiomatic meaning.

Verification / Alternative check:
Consider the sentence The workers pulled the rope with might and main to move the heavy load. Replacing with might and main by with full force keeps the meaning strong and clear: they used all their strength. Substituting with full risks or with full blessings does not fit naturally, because the context is about power, not danger or spiritual help. This comparison confirms that with full force is the correct paraphrase of the idiom.

Why Other Options Are Wrong:
With full risks: Emphasises possible danger or loss, not the amount of effort applied.
Having full confidence: Describes positive belief, which may exist even when the effort is weak.
With full blessings: Suggests approval or support from others, not the direct strength with which a task is done.

Common Pitfalls:
A common error is to pick a generally positive sounding phrase without matching it to the specific focus of the idiom. Since might and main both relate to strength, any correct paraphrase must talk about effort or force. To improve performance on idiom questions, learners should link each expression to a simple core idea. For this idiom, that core idea is full strength. Keeping such mental labels will help you quickly reject options that are about confidence, luck, or risk rather than effort.

Final Answer:
The idiom With might and main means doing something with full force, so option b is correct.