Let us consider total no of population is 100.
It is given total population doesn't change remain same both years.
in 2001
no of male=60
Literate male= 50%of 60=30
No of females= 40
Literate females= 40% of 40=16
So total literate in 2001=30+16=46
in 2011
no of male are 50% so 50
Literate male= 60% of 50= 30
No of females= 50
Literate females= 60%of 50=30
So total literate in 2011= 30+30=60
percentage change in literate population from 2001 to 2011
=( Total literate in 2011-total literate in 2001)*100/total literate in 2001
=( 60-46)*100/46= 1400/46= 30.43%
Answer A