In a given context, how many control valves typically control the motion of the boom and bucket cylinders in block C?

Typically, two control valves are used to manage the motion of the boom and bucket cylinders in hydraulic systems, such as those found in excavators or similar machinery. Each valve operates independently to control the flow of hydraulic fluid to a specific cylinder, allowing for precise movements of both the boom and the bucket.

The use of two valves enables simultaneous functionality; for example, while one valve controls the boom's ascent or descent, the second valve can simultaneously manage the bucket's tilting or lifting. This configuration enhances operational efficiency, allowing the operator to perform complex maneuvers with greater control.

In contrast, having just one valve would limit the ability to manage the two cylinders independently, potentially resulting in less effective operation. More than two valves would be unnecessary for this function, as it would complicate the hydraulic system without providing additional benefits for the basic control of the boom and bucket. Thus, using two control valves strikes an optimal balance between functionality and complexity in controlling the respective movements in block C.