To solve the subtraction equation \( 697.3 - 477.7 \), we can use the fact that \( 219.6 + 477.7 = 697.3 \).
So, we can rearrange the addition as follows: \[ 697.3 - 477.7 = 219.6 \]
Thus, the answer to \( 697.3 - 477.7 \) is \( 219.6 \).
The correct answer is B. 219.6.