Question

the classical period of molecular biology began in 1953 with 1)the discovery of DNA by F. meischer 2)the discovery of molecular structure of (double helical model of) DNA by watson and crick 3)the discovery of transforming principle (experiment genetic material by Griffith and his Cowokers) 4)conformation of genetic nature of DNA by Hershey and Chase

Answer 1

the classical period of molecular biology began in 1953 with the discovery of D.N.A. by friedrich meischer.