Answer:
4
Explanation:
The greatest common factor (GCF) is the highest factor of two numbers...
4 (4) = 16
3 (4) = 12
4 is a factor of both 12 and 16. It is also the greatest factor of the two numbers. For example, 2 is also a factor of 12 and 16. However, it is not the greatest number... 4 is.