Step 1: Concept
In a regular hexagon, the distance from the center $O$ to any vertex is $r$.
Step 2: Analysis
Fields due to opposite pairs:
- At A(+q) and D(+q): Fields cancel out at $O$.
- At B(-q) and E(+Q): Net field depends on $Q$.
- At C(-q) and F(-q): Fields cancel out at $O$.
Step 3: Calculation
The problem implies that after cancellation, the net field due to the five charges is twice the field of E. Through geometric symmetry and the condition given, the magnitude $Q$ must balance or multiply correctly with $q$.
Step 4: Conclusion
For the specific vector sum described in this configuration, $Q = q$.
Final Answer: (B)