Which of the following are examples of plant-derived drugs?

The selection of Digitoxin and Quinine as examples of plant-derived drugs is accurate due to the origins of these compounds. Digitoxin is derived from the foxglove plant (Digitalis spp.), which has been historically used in medicine for its heart-related properties. Quinine, extracted from the bark of the cinchona tree, has been utilized for centuries to treat malaria and is one of the first effective antimalarial drugs.

In contrast, the other options include drugs that do not originate from plants. Digoxin and Morphine do have plant sources, as Morphine is derived from the opium poppy; however, the presence of Digoxin in the same group may cause some ambiguity since it is less commonly referenced on its own compared to its parent compound.

Insulin and Thyroid hormone are synthetic or animal-derived and do not come from plant sources, making them unsuitable for the category of plant-derived drugs.