What will come in the place of the question mark (?) in the following equation, if '+' and '−' are interchanged and '×' and '−' are interchanged? 59 + 39 − 63 × 21 − 26 = ?

After interchanging '+' with '−' and '×' with '÷': the equation becomes 59 − 39 + 63 ÷ 21 + 26 = 59 − 39 + 3 + 26 = 49 + 3 + 26 = 78. Re-reading: '+' and '−' are interchanged, and '×' and '÷' are interchanged. So: 59 − 39 + 63 ÷ 21 + 26 = 20 + 3 + 26 = 49. The answer key gives 98 (option c).