Final answer:
In the 1920s and 1930s, the emergence of radio broadcasting and the momentum of the suffrage movement were significant factors in the convergence of change affecting polling.
Step-by-step explanation:
The era of the 1920s and 1930s did see a convergence of change that impacted polling. Among the factors in this convergence were:
- The emergence of radio broadcasting, which marked the start of popular culture and an American mass identity, a medium that could reach the masses simultaneously and sway public opinion.
- The suffrage movement gaining momentum, with activities that highlighted the cause for women's voting rights.
It is important to note that while the telegraph was important for data transmission, its peak usage was before the 1920s, and the early internet forums did not exist in that timeframe.