Step 1: Geometric Mean Formula.
The geometric mean (GM) for \( n \) values \( x_1, x_2, \dots, x_n \) is calculated as:\[GM = \left( \prod_{i=1}^n x_i \right)^{\frac{1}{n}}\]
Step 2: Calculation.
For the set of values {2, 4, 8}, the geometric mean is:\[GM = (2 \cdot 4 \cdot 8)^{\frac{1}{3}}\]\[GM = (64)^{\frac{1}{3}} = 4\]
Step 3: Result.
The geometric mean of 2, 4, and 8 is 4. Therefore, option (C) is correct.