Final answer:
The synonym for digitalis is foxglove, which is known for its bell-shaped flowers and medicinal uses, making 'foxglove' the correct answer.
Step-by-step explanation:
The synonym for digitalis is Foxglove (option 1). Digitalis refers to a genus of flowering plants, and foxglove specifically refers to plants in the Digitalis genus. Foxglove plants contain compounds used in medicine, particularly in the creation of medications for heart conditions. While lilies, daisies, and roses are distinct types of flowers, the term "digitalis" is specifically associated with plants like foxglove in the botanical context, and using "Foxglove" as a synonym aligns with its usage in medicinal and botanical contexts.