The system of equations 2x + 4y = 6 and 4x + 8y = 8 is

1. Consistent with a unique solution
2. Consistent with infinitely many solutions
3. Inconsistent
4. None of the above

When there is no solution, the equations are called inconsistent. This happens, when the lines are parallel.

Here, a1/a2 = b1/b2 = 1/2 ≠ c1/c2

So, the two lines are parallel.

The correct option is C.