Introduction:
In ancient times, various herbs and plants were used for medicinal purposes. Some of these plants are still used today for their therapeutic properties. This question asks us to identify the plant that was not used in ancient times for making drugs and is not used for the same purpose now. The correct answer is option 'A', Marigold.

Explanation:
Here, we will discuss the medicinal uses of the three plants mentioned in options 'B', 'C', and 'D' to understand why they were used in ancient times and are still used today.

1. Foxglove:
- Foxglove, scientifically known as Digitalis purpurea, is a flowering plant that contains several compounds called cardiac glycosides.
- These compounds have the ability to strengthen the contractions of the heart muscles and regulate the heart rate.
- In ancient times, foxglove was used to treat heart and circulatory disorders.
- Today, it is still used to treat certain heart conditions, such as congestive heart failure and atrial fibrillation.
- The active compounds present in foxglove are used to produce drugs like digoxin and digitoxin, which are prescribed by doctors.

2. Belladonna:
- Belladonna, also known as Atropa belladonna, is a perennial herbaceous plant.
- It contains various alkaloids, including atropine, scopolamine, and hyoscyamine, which have anticholinergic properties.
- In ancient times, belladonna was used as a sedative, pain reliever, and to dilate pupils.
- Today, it is still used in certain medications for its antispasmodic and analgesic properties.
- Belladonna alkaloids are used in the treatment of conditions like irritable bowel syndrome, motion sickness, and eye conditions requiring pupil dilation.

3. Castor Oil:
- Castor oil is derived from the seeds of the castor oil plant, scientifically known as Ricinus communis.
- It has been used for centuries for its various medicinal properties.
- In ancient times, castor oil was used as a laxative to relieve constipation.
- It is still used today as a laxative and is also used topically for its anti-inflammatory and antibacterial properties.
- Castor oil is found in numerous over-the-counter products, including creams, ointments, and cosmetics.

Conclusion:
Marigold, the plant mentioned in option 'A', is not known for its medicinal uses. While marigold has some therapeutic properties, it is primarily used for ornamental purposes and as a natural dye. Thus, it is the plant that was not used in ancient times for making drugs and is not commonly used for the same purpose now.

Your answer is D shivani