According to the passage on energy and civilisation, what will the survival of humankind mainly depend on in the coming era of limited and expensive energy?

Introduction / Context:
This question asks you to identify the key solution proposed in the passage for dealing with the global energy crisis. The passage warns that fossil fuel reserves are finite and that their depletion will lead to scarcity and high prices. It clearly states that, for humans to survive on this planet, there must be a transition to sustainable energy sources. The question tests whether you have grasped this central recommendation rather than focusing only on the description of the problem.

Given Data / Assumptions:

• Oil, natural gas, and coal supplies are limited and will eventually be exhausted.
• As these fuels become scarce, they become expensive, causing a worldwide energy crisis.
• The passage explicitly states that if humans are to survive, they must move to sustainable energy sources.
• It contrasts a planned transition with a forced, chaotic one and stresses that understanding the crisis is crucial for survival.

Concept / Approach:
The central idea is not simply to maximise use of existing resources, which would accelerate depletion, nor to keep production constant, which is impossible as wells and mines run dry. Regulation of consumers might help temporarily but does not solve the root problem of finite resources. Instead, the passage emphasises switching from finite fossil fuels to renewable, sustainable sources such as wind and solar power. Therefore, the survival of humankind depends mainly on managing this transition successfully.

Step-by-Step Solution:
Step 1: Identify the main recommendation in the passage, which is to make a transition to sustainable energy sources. Step 2: Note that the author states clearly that if humans are to survive, this transition is necessary. Step 3: Examine option b, transition to sustainable energy resources, and see that it exactly matches this recommendation. Step 4: Check option a, maximum use of available energy resources, which would worsen depletion and is not suggested as a solution. Step 5: Check option c, regulation placed on energy consumers, which may be part of policy but is not presented as the central condition for survival. Step 6: Check option d, keeping the level of energy production constant, which the passage itself says will be impossible as resources decline. Step 7: Conclude that option b is the only one consistent with the passage argument.

Verification / Alternative check:
Summarise the author solution in one sentence: To avoid extinction and survive the coming energy crisis, humans must shift from finite fossil fuels to sustainable energy sources, preferably in a planned way. This summary clearly matches the wording of option b. None of the other options captures both the idea of transition and the emphasis on sustainability. This confirms the correctness of option b.

Why Other Options Are Wrong:
Maximum use of available energy resources would speed up depletion and is contrary to the warning in the passage. Regulation placed on energy consumers may have some effect but is never presented as the main condition for survival. Keeping the level of energy production constant is unrealistic given declining resource output and does not address the need to change the type of energy sources used.

Common Pitfalls:
Some candidates focus only on conserving current resources and choose options about regulation or maximum use without thinking about long term sustainability. Others may misread the passage and assume that simple efficiency is enough. To avoid such mistakes, always pay attention to explicit statements about what must be done in the future and look for words like transition, sustainable, or long term in the text.

Final Answer:
According to the passage, the survival of humankind will depend mainly on a transition to sustainable energy resources.