The "Open Door Policy" in China was announced by :-

Deng Xiaoping in 1978

The correct answer is Option 1- Deng Xiaoping in 1978.

The Chinese leadership took major policy decisions in the 1970s. China ended its political and economic isolation with the establishment of relations with the United States in 1972. Premier Zhou Enlai proposed the ‘four modernisations’ (agriculture, industry, science and technology and military) in 1973. By 1978, then-leader Deng Xiaoping announced the ‘open door’ policy and economic reforms in China. The policy was to generate higher productivity through investments of capital and technology from abroad.