According to the provisions in the Income Tax Act, 1961 pertaining to income under the head 'Salaries', 'Underground allowance' granted to an employee who is working in uncongenial, unnatural climate in underground mines is exempted up to ______.
1
Rs. 500 per month
2
Rs. 1,200 per month
3
Rs. 1,600 per month
4
Rs. 800 per month