In order for them to work, what must the control rods in a nuclear reactor contain? a. neutron-emitting material b. neutron-absorbing material c. uranium-235 d. water

The correct answer is option B which is neutron absorbing material.

Explanation:

In nuclear reactors, uranium absorbs a neutron, broke into two nuclei and releasing 3 more neutrons and energy. These neutrons further absorbed by other uranium atoms.

Control rods are used to control the fission reaction in nuclear reactors by absorbing neutrons.

Hence the material used in control rods is neutron absorbing material.

colorless gas, exhibiting a blue glow when placed in an electric field

b) solid

its a type of rock