Answer:
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.
And
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.
Qiyas. In Islamic law, the deduction of legal prescriptions from the Quran or Sunnah by analogic reasoning.
Ijma. Consensus or agreement. One of four recognized sources of Sunni law.
Ijtihad. Islamic legal term meaning “ independent reasoning,”