The correct representation of the combined gas law is:
\[ \frac{P_1 V_1}{T_1} = \frac{P_2 V_2}{T_2} \]
This can also be rearranged in terms of equality of ratios, but typically it is represented by the above equation. To match the format you presented, you could write it as:
\[ P_1 V_1 T_2 = P_2 V_2 T_1 \]
However, since that option is not among your choices. The statement that directly represents the relationship without rearranging is:
V1P1T1 = V2P2T2
This option is usually interpreted as maintaining the same ratio under the combined conditions expressed by the different states. However, if strict adherence to the combined gas law format is needed, ensure clarity that it refers to \( \frac{P V}{T} \).
If you need to pick from one of your specific options, "V1P1T1 = V2P2T2" is the closest correct representation when rearranged properly.