Answer:
option B and C
Explanation:
Control rod are used to regulate the nuclear reactor.
When you insert control rod in the reactor it slows down the nuclear fission inside the reactor and the energy produced in the reactor will be less.
When you remove control road from the reactor the nuclear fission increase inside the reactor and the energy production is high.
Control rod consist of boron, boron absorb the neutron which help to control the nuclear fission.
Hence, the correct answer is option B and C
