Correct Answer - Option 3 : 1845

**Given **

The average of four consecutive number = 42

**Formula used **

Average = Sum of observation/No. of observation

**Calculation **

Let the four consecutive odd number be x, x + 2, x + 4, x + 6

Sum of four consecutive number = 42 × 4 = 168

⇒ 4x + 12 = 168

⇒ x = 39

So, B = x + 2 = 41

and D = x + 6 = 45

Product of B and D = 41 × 45 = 1845

**∴ The required answer is 1845**