Final answer:
The common ratio of the geometric sequence 4, 8, 16, ... is 2, computed by dividing any term by its preceding term.
Step-by-step explanation:
To find the common ratio of a geometric sequence, you divide any term by the previous term. In the sequence provided (4, 8, 16, ...), you can divide the second term (8) by the first term (4), which equals 2. Likewise, if you divide the third term (16) by the second term (8), the result is also 2. This shows that the sequence is indeed geometric and the common ratio is 2, which is the factor by which each term is multiplied to get to the next term in the sequence.