Final answer:
The amplitude of the object in simple harmonic motion is 4.0 cm, which is the maximum displacement from its equilibrium position.
Step-by-step explanation:
The amplitude of an object in simple harmonic motion (SHM) is defined as the maximum displacement from the object's equilibrium position. In the scenario provided, the object has an amplitude of 4.0 cm. Therefore, the amplitude of the object is 4.0 cm, which corresponds to option 2).
Amplitude is an important property of SHM, as it helps determine characteristics like the object's maximum potential energy and maximum speed during motion.