Statement 1 is correct: Viruses that infect bacteria are known as bacteriophages or phages. These viruses use bacterial cells as hosts to replicate and propagate.

Statement 2 is correct: Certain viruses, called mycoviruses, can infect and replicate within fungal cells, using them as hosts.

Statement 3 is correct.Viruses that infect plants are known as plant viruses. They can hijack the cellular machinery of plant cells to replicate and spread within the plant.

Hence, option D is the correct answer.