Pyrex glass is obtained by fusing together.........
(A) 60 to 80% Al2O3, 10 to 25% SiO2 and remaining amount of B2O3
(B) 60 to 80% B2O3, 10 to 25% Al2O3 and remaining amount of SiO2
(C) 60 to 80% SiO2, 10 to 25% B2O3 and remaining amount of Al2O3
(D) 60 to 80% SiO2, 10 to 25% Al2O3 and remaining amount of B2O3