Which of the following are used by plants to reproduce asexually?

Many spores are stored in sacs called sporangia and when these sporangia burst, minute single-celled, thin, or thick-walled structures called spores are released. Thus, spores are microscopic reproductive bodies. They are the agents of asexual reproduction, whereas gametes are agents of sexual reproduction. 

Spores are produced by bacteria, fungi, algae, and plants.