Which of the following is the common name for Physocarpus opulifolius 'Diablo'?

Physocarpus opulifolius 'Diablo' is commonly known as Diabolo Ninebark. This ornamental shrub is renowned for its striking dark purple foliage and attractive peeling bark, making it a popular choice in landscape design for adding color and texture. The name "Ninebark" comes from the characteristic layering of its bark, which peels in strips.

The other names provided do not correspond to this plant; Golden Purslane refers to a different type of succulent plant known as Portulaca oleracea. Purple Leaf Sand Cherry, scientifically known as Prunus x cistena, is another separate species with similar foliage color but is not the same plant as Ninebark. Lastly, Red Maple, or Acer rubrum, is a completely different tree species known for its vibrant fall color and is unrelated to the characteristics of Diabolo Ninebark. Thus, the common name for Physocarpus opulifolius 'Diablo' is unequivocally Diabolo Ninebark.