What reference plane is established parallel to the ship's centerline?

The correct answer is based on the concept of reference planes used in naval architecture and fire control systems. The reference plane that is established parallel to the ship's centerline is typically identified as the "Master reference plane." This serves as the primary reference for various measurements and alignments aboard the vessel.

In contrast, the choice that specifies "Parallel to SBP by MLP on lower deck" represents a more specific context where a sub-reference plane is established in relation to the ship's baseline. This refers to a specific plane utilized for certain measurements on the lower deck, but it does not directly identify the primary reference plane as being parallel to the centerline of the ship in a general sense.

The term "Foundation roller path plane" refers to a plane related to the positioning of foundation structures for rolling components and equipment, and "Skewed center" implies an offset or angled alignment rather than a parallel plane with the centerline.

Therefore, understanding that the Master reference plane is the essential baseline for alignment and measurement confirms why it is identified as the answer relating to being parallel to the ship's centerline.