Answer:
Both of them.
Explanation:
By low or high spin complex we refer to all spins in the system (complex) aligned either up or down, which is normally simulated in Ising model. It means that all spins aligned, either up or down, like this:
∧ ∧∧ ∧∧ ∧∧ ∧
║║║║║║║║
(Those are arrows pointing up) are a stable configuration (lowest energy), as it actually occurs in ferromagnetic materials.
