What is the primary characteristic of softwood?

Softwood primarily comes from coniferous trees, which typically have a lower density compared to hardwoods, or those that come from deciduous trees. This characteristic of lower density means that softwoods are generally lighter and can be easier to work with for various applications, such as construction and furniture making.

The structure of softwood consists of simpler and less dense wood fibers, which contributes to its lighter weight. This makes softwoods like pine, spruce, and fir especially useful in situations where weight is a crucial factor, such as in building frameworks and shipping materials.

While "stronger" and "more durable" qualities may be present in some softwood species, they do not generally surpass hardwoods in these aspects. Hardwoods, with their denser structure, often provide greater strength and durability attributes, making them favored for long-lasting furniture and flooring applications.

Hence, the defining feature that separates softwoods from hardwoods is their characteristic of having lower density than most hardwoods, which is why this option is the most accurate.