The number of digits in the successor of the greatest 4-digit number is____.

Options

A. 4
B. 5
C. 3
D. 6

Explanation

To solve the question, "The number of digits in the successor of the greatest 4-digit number is____," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Greatest 4-Digit Number:**
The greatest 4-digit number is 9999.

2. **Find the Successor:**
The successor of a number is obtained by adding 1 to that number. So, we calculate:
\[ 9999 + 1 = 10000 \]

3. **Count the Number of Digits:**
Now we need to determine how many digits are in the number 10000. We can count the digits:
- 10000 has 5 digits (1, 0, 0, 0, 0).

4. **Conclusion:**
Therefore, the number of digits in the successor of the greatest 4-digit number (which is 10000) is 5.

### Final Answer:
The number of digits in the successor of the greatest 4-digit number is **5**.

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