The group of plants that possess leaf tendrils are Peas and Glory lily.
Let's discuss each option and why they are either part of the group or not.

a) Peas, Glory lily:
- Peas belong to the Fabaceae family, which is commonly known as the legume or pea family. These plants have a characteristic leaf structure called tendrils, which are slender, coiled structures that help the plant to climb and support itself. Pea plants use their leaf tendrils to attach themselves to trellises or other supporting structures.
- Glory lily, also known as Gloriosa superba, is a climbing plant that belongs to the family Colchicaceae. It also possesses leaf tendrils that assist in climbing.

b) Cucumber, Pumpkin:
- Cucumber and pumpkin belong to the Cucurbitaceae family, which includes many vine plants. However, they do not possess leaf tendrils. Instead, they use their long, spiraling stems to climb and support themselves. These plants are called "tendril climbers" because they produce tendrils on their stems rather than their leaves.

c) Watermelon, Grape vine:
- Watermelon and grape vine belong to the family Cucurbitaceae and Vitaceae, respectively. Like cucumber and pumpkin, they are also vine plants but do not possess leaf tendrils. Instead, they use their long, slender stems to climb and support themselves.

d) All of these:
- This option is incorrect because watermelon and grape vine do not possess leaf tendrils. Only peas and glory lily have leaf tendrils among the given options.

In conclusion, the correct answer is option 'A' - Peas and Glory lily. They are the only plants among the given options that possess leaf tendrils, which are specialized structures for climbing and support.