Which statement is correct for synchronous machine comparative to induction machine? 

The correct answer is option 2):(The speed is independent of load. )

Concept:

Synchronous machine

• A synchronous machine is a doubly excited machine
• Synchronous motors are not self-starting motors. This property is due to the inertia of the rotor; it cannot instantly follow the rotation of the magnetic field of the stator.
• A synchronous motor is capable of operating at all types of power factors i.e. either UPF, leading, or lagging power factor. 
• A synchronous motor either runs at synchronous speed or not at all, i.e., while running, it maintains a constant speed from no-load to full load. The speed of a synchronous motor is independent of load

Induction motor:

• The induction motor is not a strictly constant-speed motor. At no load, it rotates at almost the synchronous speed (120 f/p rpm). As load increases, it needs to generate torque to drive the load. This is possible only if an induced current flows in the rotor and this requires that a slip must exist between the rotor speed and the synchronous speed. Normally, maximum torque is produced at 5% slip, i.e. 95% of synchronous speed. Thus we can say that an induction motor is a nearly constant-speed motor.
• The induction motor has to draw more magnetizing current to maintain a constant flux.The motor operates only at a lagging power factor. 
• An induction motor is a single exciting machine. Its stator winding is energized by an AC source. 
• Three-phase induction motor is self-starting because winding displacement is 120 degrees for each phase and the supply also has 120 phase shift for the 3-phase. It results in a unidirectional rotating magnetic field developed in the air gap which causes the 3-phase induction motor to self-start.

​Therefore option 2 is a correct  statement about synchronous machines comparative to induction machine