Refer to figures.
Once a helicopter leaves the ground, it is acted upon by four aerodynamic forces:

• Thrust;
• Drag;
• Lift and
• Weight.

An important consequence of producing thrust is Torque.

As a result, in accordance with Newton's Third Law, as the engine turns the main rotor disk in a certain direction (rotor propulsion), the helicopter fuselage wants to turn to the opposite.

To counteract this torque-induced turning tendency (reactive force), an anti torque rotor or tail rotor is incorporated into most helicopter designs.

However, a “tandem or dual rotor” helicopter has two large horizontal rotor assemblies instead of one main assembly and a smaller tail rotor, turning in opposite directions.

The rotors both use the same drive system, so they have the same RPM and won’t hit each other.

Additionally, the rear rotors are set higher than the front ones, on a pylon so they don’t catch their dirty air (mostly).

Finally, a significant advantage of tandem rotors is that all of the power from the engines can be used for lift, whereas a single rotor helicopter uses power to counter the torque.

Therefore, I is incorrect and II is CORRECT.