Correct option is A
Given: 5 + 9 × 3 ÷ 2 – 1 = ?
After interchanging the signs '÷' and ‘-', and interchanging the numbers '3' and ‘2’ we get following equation-
5 + 9 × 2 - 3 ÷ 1 = ?
Applying the BODMAS rule-
5 + 9 × 2 - 3 = ?
5 + 18 - 3 = ?
5 + 18 - 3 = ?
23 – 3 = ?
? = 20
Thus, the correct answer is (a) 20.