Which plant produces the most suitable amount of oxygen for humans to live on Mars?

Question

+ Soil
+ Temperature
+ pH
What else?

PS: This is a serious question, thanks!

Answer 1

Trees

Answer 2

Radiation
Water
Light
Carbon source
Nitrogen source
Phosphat source
Ooson layer (O3) (going togather with Radiation )
molecular oxigen (02)

if you want a plant wich can produce you the Oxigen and can survive ruff conditions , as much as funny as it is , the Canabis is best for that (and i am 100% seriouse)

if you want more details you can contact me on MSN messenger [e-mail]

i am Medical biotechnologist and envierment scientist and i would love to help.