After fertilization, the ovule and ovary undergo changes to form the seed and fruit, respectively. Option 1 is the correct answer.

Option 1: Seed and fruit respectively - This option correctly states that after fertilization, the ovule develops into a seed, which contains the embryonic plant. The ovary, on the other hand, develops into a fruit, which surrounds and protects the seed.

Option 2: Fruit and seed respectively - This option is incorrect. It swaps the development of the ovule and ovary. The ovule develops into a seed, and the ovary develops into a fruit.

Option 3: Seed and flower respectively - This option is incorrect. It confuses the development of the ovule and flower. After fertilization, the ovary develops into a fruit, not the flower. The flower is the reproductive structure that produces the ovule.

Option 4: Degenerated ovule and seedless fruit respectively - This option is incorrect. It suggests that the ovule degenerates and does not develop into a seed, which is not true. A seedless fruit may occur due to various factors, but it does not mean that the ovule degenerates.