Please provide a detailed solution for this question.........

Hai ANMOL SETH,
The answer is Guanine-A option

The synthesis of m-RNA from DNA is called as called Transcription.
During the Above process the DNA sequenceis converted to RNA sequence.

Let us see an small example
For a sequence in DNA with sequence G-G-G-C-C-C-A-A-A-T-T-T-
The sequenceof RNA (m-RNA / r-RNA / t-RNA) formed will be C-C-C-G-G-G-U-U-U-A-A-A-