Potato and brinjal belong to the genus

The correct option is Solanum.

Let us break down the scientific classification of potato and brinjal to understand why they belong to this genus:
1. Potato is scientifically known as Solanum tuberosum.
2. Brinjal (also known as eggplant) is scientifically known as Solanum melongena.

In binomial nomenclature, the first word of a scientific name represents the genus to which the organism belongs. Since both potato (Solanum tuberosum) and brinjal (Solanum melongena) share the first word Solanum, they belong to the genus Solanum.

Here is a brief look at the other options to understand why they are incorrect:
- Allium: This genus includes onions (Allium cepa) and garlic (Allium sativum).
- Brassica: This genus includes mustard (Brassica nigra), cabbage, and broccoli.
- Mangifera: This genus includes mango (Mangifera indica).