ANS:E - All the above.

1. If the ratio of depth to width is less than 2, it is shallow foundation: This statement suggests that a foundation is considered shallow if the ratio of its depth to width is less than 2. Shallow foundations typically include footings and raft foundations, where the depth of the foundation is relatively small compared to its width.
2. If the ratio of depth to width is more than 2, it is deep foundation: This statement indicates that a foundation is classified as deep if the ratio of its depth to width exceeds 2. Deep foundations, such as piles and drilled shafts, are designed to transfer building loads to deeper, more competent soil or rock layers below the ground surface.
3. If the ratio of the length to width is between 1 and 2, it is spread foundation: This statement suggests that a spread foundation, such as a mat or raft foundation, typically has a length-to-width ratio between 1 and 2. Spread foundations distribute building loads over a larger area of soil to prevent excessive settlement.
4. If the length is large as compared to width, it is a strip foundation: This statement implies that a foundation is considered a strip foundation when its length is significantly larger than its width. Strip foundations are long and narrow footings that support load-bearing walls or lines of columns.

Given that all the statements describe different types of foundations and their defining characteristics based on ratios of dimensions, "All the above" is the correct choice. Each statement highlights a criterion used to classify different types of foundations in structural engineering.