The specific sequence of DNA that initiate replication of alien DNA in rDNA technology is called as :

Origin of replication

The correct answer is Option (2) -Origin of replication

The specific sequence of DNA that initiates replication of alien DNA in rDNA technology is called origin of replication.

This is a sequence from where replication starts and any piece of DNA when linked to this sequence can be made to replicate within the host cells. This sequence is also responsible for controlling the copy number of the linked DNA.

The origin of replication is a short DNA sequence that is essential for the initiation of DNA replication. It contains specific sequences that are recognized by proteins that bind to the origin and initiate the replication process.

In rDNA technology, the origin of replication is used to initiate the replication of alien DNA that has been introduced into a cell. The alien DNA is typically inserted into a plasmid, which is a small circular DNA molecule that can replicate independently of the host cell's DNA. The plasmid contains an origin of replication that is recognized by the host cell's replication proteins. Once the replication proteins bind to the origin of replication on the plasmid, they initiate the replication of the alien DNA.

The origin of replication is a critical component of rDNA technology. Without the origin of replication, the alien DNA would not be able to replicate and would not be passed on to the cell's offspring.