Which of the following advances in food production were attributed to the Green Revolution of the 1960s and 1970s? a. Improved land availability b. Drought-resistant varieties of crop plants c. Improved irrigation systems d. Genetically engineered crops

During the Green Revolution of the 1960s and 1970s, several significant advances were made in food production to increase crop yields and feed a growing global population. The advances that are commonly attributed to this period include:

b. Drought-resistant varieties of crop plants - Scientists developed high-yielding varieties of wheat, rice, and other crops that were better adapted to a variety of growing conditions, including drought resistance. This allowed for more reliable harvests in regions that were previously susceptible to crop failure due to lack of water.

c. Improved irrigation systems - Alongside the development of new crop varieties, there were significant improvements in irrigation technology and practices, which enabled farmers to provide consistent and sufficient water to their crops, enhancing their ability to grow food in areas with unreliable rainfall.

Although improved land availability (a) and genetically engineered crops (d) are also important factors in food production, they are not typically considered direct outcomes of the Green Revolution. Land availability improved as a result of various other socio-economic factors and policy changes, while genetically engineered crops became prominent much later, starting in the 1980s and 1990s, well after the traditional timeframe of the Green Revolution.