Correct Answer: 4 – 3 × 9 = 3

Solution : Let's check each option –
First Option: 9 – 4 × 3 = 21
On interchanging the mathematical signs and numbers, we get –
9 × 3 – 4 = 21
L.H.S. = 9 × 3 – 4 = 27 – 4 = 23
L.H.S. ≠ R.H.S.
Second Option: 4 – 3 × 9 = 3
On interchanging the mathematical signs and numbers, we get –
3 × 4 – 9 = 3
L.H.S. = 3 × 4 – 9 = 12 – 9 = 3
L.H.S. = R.H.S.
Third Option: 3 × 4 – 9 = 9
On interchanging the mathematical signs and numbers, we get –
4 – 3 × 9 = 9
L.H.S. = 4 – 3 × 9 = 4 – 27 = –23
L.H.S. ≠ R.H.S.
Fourth Option: 3 × 9 – 4 = 4
On interchanging the mathematical signs and numbers, we get –
4 – 9 × 3 = 3
L.H.S. = 4 – 9 × 3 = 4 – 27 = –23
L.H.S. ≠ R.H.S.

So, only the second option satisfies the equation. Hence, the second option is correct.