Over-irrigation can lead to:

The correct answer is: d) All of the above

Over-irrigation can lead to waterlogging, salinization, and reduced crop yields.

Waterlogging occurs when the soil becomes saturated with water, which can lead to the growth of anaerobic bacteria that can damage plant roots.

Salinization occurs when the soil becomes too salty, which can also damage plant roots and make it difficult for plants to absorb water.

Reduced crop yields occur when plants are not able to grow properly due to waterlogging or salinization.

Over-irrigation can also lead to other problems, such as soil erosion and the loss of nutrients. It is important to irrigate crops properly to avoid these problems.