Which components are part of an excavator's boom?

The correct answer identifies the components of an excavator's boom as the boom arm, stick, and bucket.

In an excavator, the boom arm is the primary structure that extends from the machine to reach outwards, over the work area. Attached to the end of the boom arm is the stick, which further extends the reach of the excavator and allows for more precise digging and operation. At the end of the stick is the bucket, used for digging and moving material.

These three components work in unison to give the excavator its capability to perform various tasks such as digging, lifting, and moving materials. Understanding this configuration is critical for operators to maximize efficiency and safety when using the machine. Other options do not accurately consist of all the necessary components of the boom; for example, tracks are part of the undercarriage, counterweights are used for balance, and the hydraulic system powers the movements but isn't a part of the boom structure itself.