Step 1: Recall the Census definition of literacy.
Literacy Rate is the share of people who can read and write with understanding, counted from a specific minimum age onward.
Step 2: Recall the exact age cutoff.
The Indian Census counts literacy for the population aged 7 years and above, not from 8, 9 or 10 years.
Step 3: Final answer.
Hence, the blank should read 7 years, option (A).