Two crystalline allotropic forms of sulphur (Sα and Sβ) can change reversibly between themselves with slow heating (above 369 K) or cooling.
Sα
(Rhombic)
>369K
⇌
Cooling
Sβ
(Monoclinic)
So, statement 1 is true. At room temperature or at standard conditions of pressure and temperature, rhombic sulphur is the thermodynamically most stable crystalline allotrope of sulphur (∆fH∘=0). So, statement II is false.