The correct answer is (b), Uttar Pradesh.
According to the Census 2011, the literacy rate of males in Uttar Pradesh was 79.7%, while the literacy rate of females was 59.5%. This means that the difference between the literacy rates of males and females in Uttar Pradesh was 20.2%.
Kerala (a) had a literacy rate of 94.0% for males and 91.9% for females, a difference of 2.1%. Mizoram (c) had a literacy rate of 91.5% for males and 93.9% for females, a difference of 2.4%. Gujarat (d) had a literacy rate of 89.3% for males and 79.1% for females, a difference of 9.2%.
The high illiteracy rate of females in Uttar Pradesh is due to a number of factors, including poverty, lack of access to education, and social and cultural norms that discourage girls from attending school. The government has taken a number of steps to address the issue of female illiteracy in Uttar Pradesh, including providing free education to girls, building more schools in rural areas, and launching awareness campaigns about the importance of education for girls. However, more needs to be done to ensure that all girls in Uttar Pradesh have access to quality education.