B
While learning typical progressions in context (in the actual song) is always vital and important, there is merit to practicing a certain skill - like the ii-V7-I - over and over again until it becomes second nature. Getting the feel of the movement from one chord to the next is important, too. The standard LH voicings were novel for their time but no longer are thought of that way. They really are standard today. They are also models of simplicity and efficiency. Getting even a few of them under your fingers will allow you to "play thru" sheet music with greater ease and sophistication.

There are many books that can help here, but one that I have found invaluable because it includes great sounding practice routines as well as real "in the context of a tune" exercises etc is Jerry Coker's Jazz Piano book. It is a classic - very slim and accessible and chock full of immediately useable stuff that will make a big difference in your playing.

Now...if I only would listen to myself...