Which classification refers to the general group of Hybrid Roses?

The classification that refers to the general group of Hybrid Roses is identified as Rosa sp. The term "Rosa" is the genus that encompasses all types of roses, including not only Hybrid Roses but also many other species of roses. The 'sp.' designation indicates multiple species within the genus, signifying a broader category that can include various hybrids and cultivars developed from different species of the Rosa genus.

Hybrid Roses, being breed variations derived from different species within Rosa, fall under this classification, making Rosa sp. the correct reference. This classification helps to encompass all cultivated roses including the hybrids, thus establishing a clear scientific categorization that includes both the hybrid varieties and the species they originated from.

In contrast, the other options mentioned do not pertain to hybrid roses. Rosa banksiae refers specifically to a single species of rose known as the Lady Bank's rose, which does not encompass all hybrids. Taxus sp. relates to the genus of yews, entirely unrelated to roses, and Spiraea spp. refers to a group of flowering shrubs known as spireas, also outside the rose family. Therefore, the broader classification of Rosa sp. appropriately indicates the inclusive nature of Hybrid Roses.