glass has many unique characteristics. Considering the structure and properties of glass, the four most significant characteristics are:（）,（）,（）, and the continuity and irreversibility of property change

glass has many unique characteristics. Considering the structure and properties of glass, the four most significant characteristics are:（）,（）,（）, and the continuity and irreversibility of property change
A.brittleness
B.isotropy
C.metastability
D.no fixed melting point
正确答案：isotropy；metastability；no fixed melting point