I felt your blitz on the RVT exam was misleading. 
Axial resolution and lateral resolution are defined as differentiation of
objects along the sound beam and objects perpendicular to sound beam
respectively. I agree with shortening the pulse length and increasing transmit
frequency to improve axial res. but not lateral res. , narrowing the sound beam
and using multiple focal zones would improve lateral resolution.  Thinking of
the two resolutions together is appropriate but I think that it's important to
differentiate between the two and how they individually work to improve
resolution.
Annie Altemus