Explanation

Note (0.35)² + 0.70 + 1 = 0.1225 + 0.7 + 1 = 1.8225, which is (1.35)². Dividing by 2.25 gives 1.8225/2.25 = 0.81. Adding 0.19 gives exactly 1.00, whose square root is 1. Hence the answer is option A; the other options come from slips in the decimal division.