before television and radio, the poster was...
Does "In this era, before television and radio, the poster was the quickest and most effective means" mean:
1. Before the development of television and radio and their vast presence in people's lives, in this era the poster was the quickest and most effective means
or
2. In this era, poster was the quickest and most effective means and television and radio were the second and third quickest and most effective means?
Context:
The US government, to cite just one nation, enlisted the talents of an army of artists to publicize various causes. Edward Hopper, for example, won the United States Shipping Board’s competition with his somewhat aggressive but dynamic poster design of a working man juxtaposed with bayonets – Smash the Hun (1918). In this era, before television and radio, the poster was the quickest and most effective means of sending a message to a large population.