As per the latest census, the approximate population of Kerala is:

10 million
20 million
35 million
50 million

The correct answer is C. As per the 2021 census, the population of Kerala is 35,806,699.

Option A is incorrect because the population of Kerala is much more than 10 million. According to the 2021 census, the population of Kerala is 35,806,699.

Option B is incorrect because the population of Kerala is much more than 20 million. According to the 2021 census, the population of Kerala is 35,806,699.

Option D is incorrect because the population of Kerala is much less than 50 million. According to the 2021 census, the population of Kerala is 35,806,699.