The diagram shows an important concept in the genetic implication of DNA. Fill in the blanks A to C.

A - Transcription, B - Translation, C - Francis Crick

A. DNA $\to$ mRNA is transcription, and it is catalyzed by RNA polymerase.

B. mRNA $\to$ Protein is translation. It takes place on the surface of ribosome.

C. The complete process shown in flow chart is called central dogma, which was proposed by Francis Crick.

(2) Rosalind Franklin gave the X-ray diffraction data on which the famous double-helical model of DNA is based.
(3) mRNA $\to$ Protein is translation 

(4) Erwin Char gaff, discovered that in DNA, the amount of adenine equals thymine, and the amount of cytosine equals guanine, known as Char gaff's rule, which is crucial for understanding DNA structure.