According to the Census of India 2001, what was the total population of the country?

Introduction / Context:
Population figures from national censuses are fundamental data points for economics, planning and general studies. The Census of India 2001 was especially important because it was the first census after the economic reforms of the 1990s and recorded India crossing the one billion mark. This question checks whether the candidate knows the approximate total population reported in that census by asking them to identify the correct numerical value among similar looking options.

Given Data / Assumptions:

• The reference year is Census of India 2001.
• The total population is expressed using the Indian system of commas.
• Options include three different large numbers and one generic option stating none of these.
• The correct approximate figure is slightly above one billion people.
• We assume awareness that the figure is specific to 2001 and not to 1991 or 2011.

Concept / Approach:
The key idea is that by 2001 India had slightly more than 100 crore people. In international notation this is written as about 1.028 billion, while in the Indian comma style it appears as 1,02,87,37,436. The other numerical options are intentionally close to confuse candidates who do not recall the exact arrangement of digits. To select the correct answer, one should remember the standard figure quoted in most textbooks and government documents for the 2001 census.

Step-by-Step Solution:
Step 1: Recall that the Census of India 2001 recorded a total population of about 102.87 crore. Step 2: Recognise that in the Indian comma format, 102.87 crore is written as 1,02,87,37,436. Step 3: Compare this structure of digits with the options given in the question. Step 4: Observe that option b exactly matches this known population figure from the census. Step 5: Select option b as the correct answer, rejecting other values and the none of these option.

Verification / Alternative check:
As an alternative check, one can convert the Indian number 1,02,87,37,436 into crores and lakhs. The first three digits from the left are 102, representing 102 crore, followed by the lakhs and thousands places. This matches the often quoted statement that the 2001 census recorded India's population as roughly 102.9 crore people. Any number significantly lower than 100 crore or higher than 110 crore would not be consistent with this known fact, which further confirms that option b is the correct one.

Why Other Options Are Wrong:
1,02,71,01,012: This number is very close but not equal to the officially reported census figure, and small differences matter in factual questions. 10,12,52,751: This is much smaller than the known population and would correspond to only a little over 10 crore people, which is incorrect for 2001. None of these: This is wrong because one of the listed values, namely 1,02,87,37,436, does exactly match the official census statistic. Any blank option: Blank options do not describe any population figure and cannot be correct.

Common Pitfalls:
Candidates often get confused by the placement of commas and digits in large numbers, especially when reading in the Indian style. Because options are deliberately chosen to differ by only a small amount, casual guessing may lead to wrong answers. Some students also misremember the year associated with crossing one billion population and may pick an option that seems round or simple. To avoid such mistakes, it is advisable to memorise the approximate total population for at least the 1991, 2001 and 2011 censuses and to practise reading large numbers carefully.

Final Answer:
According to the Census of India 2001, the total population of the country was 1,02,87,37,436.