Find the missing number?

6
3
0
1

The answer is 1.

The missing number is the number that, when added to the other two numbers, gives a total of 10.

Option A: 6. If 6 is added to the other two numbers, the total is 12.
Option B: 3. If 3 is added to the other two numbers, the total is 9.
Option C: 0. If 0 is added to the other two numbers, the total is 8.
Option D: 1. If 1 is added to the other two numbers, the total is 10.

Therefore, the correct answer is 1.