Identify the incorrect statement.
Primary growth of plant is increase in girth of plant axis due to the activity of apical meristems.
Secondary growth is due to the activity of lateral meristems.
Elongation of stem is primary growth.
Increase in surface area of leaf is primary growth.
Increase in the girth of root and stem is secondary growth which is due to the activity of lateral meristems (vascular cambium and cork cambium).