You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
American_Broadcasting_Company

Context:
In April 1970, Congress passed the Public Health Cigarette Smoking Act which banned cigarette advertising from all television and radio networks, including ABC, when it took effect on January 2, 1971. Citing limited profitability of its cinemas, ABC Great States, the Central West division of ABC Theatres, was sold to Henry Plitt in 1974. On January 17, 1972, Elton Rule was named President and Chief Operating Officer of ABC a few months after Goldenson reduced his role in the company after suffering a heart attack.

Question:
When did the ban on cigarette advertising take effect for television networks?

January 2, 1971