The correct answer is: a) Significantly lower than the national average.
The literacy rate in Odisha is 72.8%, which is significantly lower than the national average of 77.7%. This means that there are more people in Odisha who are illiterate than in the rest of India.
There are a number of reasons for this low literacy rate. One reason is that Odisha is a relatively poor state, and many people do not have access to quality education. Another reason is that the state has a large tribal population, many of whom do not speak Hindi or English, the languages of instruction in schools.
The low literacy rate in Odisha has a number of negative consequences. It means that many people in the state are unable to find good jobs, and they are also more likely to be poor and unhealthy. The government of Odisha is working to improve the literacy rate, but it is a challenging task.
Option b) is incorrect because the literacy rate in Odisha is not slightly lower than the national average. It is significantly lower.
Option c) is incorrect because the literacy rate in Odisha is not about the same as the national average. It is significantly lower.
Option d) is incorrect because the literacy rate in Odisha is not higher than the national average. It is significantly lower.