A pilot with a cruise clearance is allowed to do which of the following?

A pilot with a cruise clearance is permitted to climb, descend, or level off within a specified block of airspace. This clearance is granted by air traffic control to allow the pilot to operate within a defined altitude range without needing to request explicit permission for each change in altitude within that block.

This flexibility is crucial for managing traffic efficiently in busy airspace and helps pilots to optimize their flight profiles, whether for fuel efficiency, safety, or to comply with different air traffic situations. The block of airspace provided by the clearance gives the pilot autonomy to navigate vertically without needing continuous communication for every adjustment made within that range, thus enhancing operational efficiency while ensuring safety standards are upheld.

The other choices do not reflect the privileges granted by a cruise clearance, as they limit the pilot's altitude adjustments or focus on specific maneuvers which do not encompass the broader permissions given by a cruise clearance.