Which type of reactor system in a nuclear steam supply system has radioactive steam and condensate?

The boiling water reactor (BWR) is the correct choice because in this type of reactor, water is both the coolant and the moderator, and it boils directly in the reactor core. This process generates steam that is radioactive due to its contact with the nuclear fission reactions taking place within the reactor. As a result, both the steam produced and the condensate, which is the steam that has been converted back to water after passing through the turbines, retain radioactivity.

In contrast, other reactor systems such as the pressurized water reactor (PWR) operate differently by using a secondary loop to produce steam. In a PWR, the primary loop contains radioactive water that is kept under pressure, preventing it from boiling, while the steam produced in the secondary loop is non-radioactive because it does not directly contact the reactor core. Fast breeder reactors and natural uranium reactors also have distinctive characteristics that do not involve the direct generation of radioactive steam and condensate in the same manner as a BWR. The design and operating principles of these systems ensure that only the BWR results in radioactive steam and condensate due to the direct connection between the reactor core and the steam generation.