My car battery is making a clicking sound and won't start. on 2008 Nissan Pathfinder

I hd battery jumped yesterday,but it wont start today.

3 answers 4 comments
Poor connection at cable(s). Or as answer 1 said battery is bad!
battery is bad
I got battery, alternator n starter tested at local AutoZone and everything tested fine.
Pretty tough job taking that starter off just to get it tested!!! Think i would have just replaced it.
They tested it with a machine.
With it still on the engine????? What was their MECHANICS suggested repair?
poss bad battery, have complete charging system ck'd out