Answer:
The correct answer will be option-A and B.
Explanation:
Transcription is a process which synthesizes a complementary molecule of DNA which acts a messenger called RNA.
The gene contains a sequence of the nucleotide at the beginning of gene called promoter sequence. The promoter sequence has the ability to attach an RNA synthesizing enzyme called RNA polymerase.
The RNA polymerase is the enzyme which synthesizes the RNA molecules using a single strand of DNA called template strand. RNA polymerase binds nucleotide at 3' end of the strand thus proceeding the strand in 5' to 3' direction.
The promoter and RNA polymerase begins the process of transcription and thus option-A and B is the correct answer.
