Indian Institute of Foreign Trade 2010 Solved Paper

Total number of subsets that can be formed with the left of 11 elements $=2^{11}=2048$
The number of subsets which contain only odd numbers(1, 3, 5, 7, 9, 11}$=2^6=64$
Number of subsets which contain at least one even integer = Total number of subsets - the number of subsets which contain only odd numbers
$\Rightarrow 2018-64=1984$
Hence, option C is the correct answer