10, 8, 13, 35, 135, 671, 4007

Options

A. 8
B. 671
C. 135
D. 13

Explanation

To find the wrong number in the series: 10, 8, 13, 35, 135, 671, 4007, we will analyze the pattern step by step.

### Step-by-Step Solution:

1. **Identify the series**: The given series is 10, 8, 13, 35, 135, 671, 4007.

2. **Look for a pattern**:
- The first two numbers are 10 and 8. We see that 10 - 2 = 8.
- The next number is 13. We can see that 8 + 5 = 13.
- The next number is 35. We can see that 13 + 22 = 35.
- The next number is 135. We can see that 35 + 100 = 135.
- The next number is 671.
- The last number is 4007.

3. **Calculate the differences**:
- From 10 to 8: 10 - 2 = 8
- From 8 to 13: 8 + 5 = 13
- From 13 to 35: 13 + 22 = 35
- From 35 to 135: 35 + 100 = 135

4. **Finding the next number**:
- To find the next number after 135, we can see that the pattern seems to be multiplying or adding larger numbers.
- The difference from 135 to the next number should be calculated.
- If we follow the pattern, we should have a number that is not 671.

5. **Continue the pattern**:
- If we check the next number after 135, we can see that if we were to follow the pattern, we would expect a number close to 669 (which is derived from the previous calculations).
- 135 + 534 = 669 (not 671).

6. **Conclusion**:
- Therefore, the number 671 is incorrect. The correct number should be 669.

### Final Answer:
The wrong number in the series is **671**.