Dispersal of Seeds by Bursting
The correct answer is option 'B' - Explosion.

Explanation:
When it comes to seed dispersal, plants have evolved various mechanisms to ensure the survival and spread of their offspring. One such mechanism is the dispersal of seeds by bursting.

How does seed bursting occur?
Seed bursting occurs when the seed pod or fruit of a plant suddenly bursts open, releasing the seeds forcefully into the surrounding environment. This burst can happen due to various factors, such as changes in temperature, humidity, or physical pressure.

Advantages of seed bursting:
Seed bursting is an effective way for plants to disperse their seeds over larger distances, increasing the chances of successful germination and growth. It helps in colonizing new habitats, reducing competition among offspring, and ensuring genetic diversity.

Examples of plants that disperse seeds by bursting:
1. Impatiens: The Impatiens plant, commonly known as touch-me-not, has seed pods that burst open when touched, flinging the seeds away from the parent plant.
2. Hura crepitans: Also known as the sandbox tree or exploding cigar tree, Hura crepitans has seed pods that explode with a loud noise, scattering the seeds up to 100 feet away.
3. Ecballium elaterium: This plant, commonly known as the squirting cucumber, has fruit that forcefully expels its seeds when the fruit is disturbed or touched.

Significance of seed bursting:
Seed bursting as a dispersal mechanism allows plants to reach new areas, expand their populations, and avoid competition with parent plants. It also increases the chances of finding suitable conditions for growth and survival.

In conclusion, seed dispersal by bursting is an effective strategy employed by certain plants to spread their seeds. This mechanism helps in the colonization of new habitats, genetic diversity, and the survival of plant offspring.