OCP CBT Question 659

Please solve the following question.

Examine the following tnsnames.ora entry:

ORCL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = sales-server)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orclpdb.example.com)
    )
  )

Which component represents the network alias?