Final answer:
Statement (b) is correct as it accurately describes a prophage during phage replication. While (c) is also correct, as Lambda phage is a temperate phage, it is not true that the majority of phages are temperate, making (a) incorrect, and thereby, (d) incorrect as well.
Step-by-step explanation:
Regarding phage replication, the correct statement is that when integrated into host DNA, the phage DNA is called a prophage. Thus, statement (b) is accurate. Phages can be classified into two main types based on their life cycles: lytic phages and temperate (or lysogenic) phages. While lytic phages enter the lytic cycle immediately upon infection, lysing the host cell and releasing newly formed phages, temperate phages can undergo a lysogenic cycle where phage DNA integrates into the host genome, remaining dormant as a prophage until certain triggers cause it to become active and enter the lytic cycle.
Lambda phage (λ phage) is indeed a well-known example of a temperate phage that can undergo both lytic and lysogenic cycles. It is not correct to state that the majority of phages are temperate since there is a wide diversity of phages with differing reproductive strategies.