Summer annuals are defined as plants that:

The definition of summer annuals accurately captures the life cycle of these plants. They germinate in the spring, allowing them to take advantage of the warmth and moisture during the summer months as they grow and develop. This growth phase culminates in flowering and setting seed by the end of summer or into fall. Once they complete their life cycle and produce seeds, they die off with the onset of cooler temperatures, typically in the fall. This cycle is crucial for the survival and propagation of summer annuals, as their seeds may then germinate the following spring, starting the process anew.

The other options do not align with the common characteristics of summer annuals. Plants that germinate in late summer and endure through winter are typically classified as winter annuals or biennials. Plants that grow year-round without seasonal cycles would be considered perennials, which persist beyond a single growing season. Lastly, the assertion that some plants only bloom in the spring fails to encompass the broader growth and life cycle aspects that define summer annuals, which are focused mainly on spring germination and summer growth.