Choose the correct statements about qiyas, ijma and ijtihad.

A. 'Ijma has been seen as a conservative instrument in the preservation of the religious heritage, and prevented the tolerant coexistence of rival scholar's view in the changing historical circumstances of the community.
B. The use of qiyas lacks a unequivocal basis in the Quran, while Tradition suggest that the Prophet may on occasion have resorted to it.
C. Although the notion of 'ijma existed from quite early times, it is debatable wherher it referred to the whole community, the Companions, the 'ulama, or just those of a particular locality, and whether it was regarded from the beginning as the infallible opinion.
D. Qiyas is the application of a ruling in a case already known, to a new case on which the law is silent, the application made possible by the presence of an illah shared by both cases.
E. Qtoiyas was applied wholesale to every pronouncement of the texts, especially on the matters of penal law, because it was always possible to find a certain "effective cause."
F. The continuous efforts of the mujtahids to deduce the law from the sources by their own efforts assured the growth of positive law.
G. It was accepted by the consensus of all legal schools that by the 13th century the gate of ijtihad had been closed to give full rein to muqallads.
H. The spread of madrasahs founded in the 11th century allowed the government to employ its own jurists on a wide scale, which marked an interference with the mujtahid's free and unfettered practice of providing legal opinions