Read the passage and answer the four questions that follow:-

Until a hundred years ago as humans, we had a simple, uncomplicated biological connect with nature. It was a straightforward equation: we drew roughly 3, 000 calories each of energy out of the Earth for our food and life's sustenance. Today that number per capita has grown to 1, 00, 000 calories. We still need only 3,000 calories each to nourish life itself. All the rest of this energy is what we extract from the Earth for everything else besides keeping ourselves alive.

How to soften this abuse of resources? What is sustainable development? How can it be started in our homes? Beyond the ceremonial planting of green and getting people to run marathons of various lengths in support of the environment, is there more that we can add to the abstract value of "sustainability"? What are the little things we can do in our day-to-day lives, to reduce the demand for things that people make and market? Of course, we know that it helps to avoid a plastic bag when you can use a newspaper bag, or a brown bag, or even a jute bag, which you can use for many more years.

However, there's actually quite a bit more than you and I can do, with very little as cost incurred, and with solutions that are very feasible and within our reach. It is possible to understand our ecological footprint and its disastrous consequences, in terms of the impact on the environment that we make.

The primary concern of the passage is _____.

we need to respect the Earth and consume less of its calories

The correct answer is Option (4) → we need to respect the Earth and consume less of its calories

The central theme and argument of the passage are built on the dramatic increase in the amount of energy (calories) humans extract from the Earth, far beyond what is needed for basic survival:

1. The Problem: The energy consumption grew from 3,000 calories (for sustenance) to 1,00,000 calories per capita, with the excess used for "everything else besides keeping ourselves alive."

2. The Solution/Concern: The passage then asks: "How to soften this abuse of resources? What is sustainable development? ...What are the little things we can do... to reduce the demand for things that people make and market?"

This clearly identifies the core concern as the excessive and abusive consumption of the Earth's resources (calories) and the need for reduction and respect (sustainability).