Hardwood flooring installation, first row question
Obviously starting and ending with a full plank is ideal, however, it almost never works out that way.  You'll want to avoid installing skinny little pieces of a plank (less than half a plank), so you'll have to make some calculations up front.

Measure the distance from wall A to wall D, then based on the width of your planks determine how many rows you'll need. You'll not want to end at wall D with a little sliver of a plank, so you may find that you have to start at wall A with a half plank to avoid that. 

You'll also want to measure from the projection in wall A, to wall A and wall D. Then determine if you started with a full plank in the projection, that you won't have a sliver along wall A or D.  

Once you have that all figured out, then you can determine the right place to start. And whether you should start with a full plank or not.

Don't forget to include expansion gaps in all your calculations.