The correct answer is option 2: Karachi. Until 1959, Karachi served as the capital of Pakistan. Karachi was chosen as the capital when Pakistan gained independence from British India in 1947. It became the economic and cultural hub of the country and played a significant role in its development. However, in 1959, the capital was shifted from Karachi to Rawalpindi due to various reasons, including the geographical location of Rawalpindi being more centrally located within the country. Later on, in 1967, the capital was moved again to Islamabad, which was purposefully constructed as a planned city to serve as the capital of Pakistan. Today, Islamabad is the official capital of Pakistan, while Karachi remains an important city in terms of business, economy, and population.