Explanation:

- First, interchange the digits 4 and 6 in the equation.

- The new equation becomes: 5 + 3 × 6 - 4 ÷ 2.

- Use the order of operations (PEMDAS/BODMAS): Parentheses/Brackets, Exponents/Orders, Multiplication and Division (from left to right), Addition and Subtraction (from left to right).

- Calculate the equation step-by-step:

1. 3 × 6 = 18

2. 4 ÷ 2 = 2

3. Insert the results back: 5 + 18 - 2.

4. 5 + 18 = 23

5. 23 - 2 = 21

- Check options: Option 2 is 21.

Thus, option 2 is correct, and .