Who was the first female Prime Minister of the United Kingdom?

Margaret Thatcher was the first female Prime Minister of the United Kingdom, serving from 1979 to 1990. She was a member of the Conservative Party and is known for her strong leadership style and significant political policies that came to be known as "Thatcherism." This included a focus on deregulation of the economy, reduction of the power and influence of trade unions, and a firm stance against the Soviet Union during the Cold War.

The other figures mentioned in the options were prominent political leaders in their respective countries, but they did not serve as Prime Minister in the UK. Angela Merkel was the Chancellor of Germany, Indira Gandhi was a Prime Minister of India, and Golda Meir served as Prime Minister of Israel. Their contributions to their countries' politics are noteworthy, but they do not relate to the context of the United Kingdom's leadership history.