Question

In an experiment to determine the effects of radiation on the germination of seeds, a factor that has to be controlled is
a.the amount of radiation.
b.the types of radiation.
c.the germination rate of seeds.
d.the amount of water added to the seeds.

Answer 1

a) is correct

because the experiment is based on radiations, not the type of radiations so it can't be b.

it can't be c because again, it's talking about the radiation

it can't be d because the water isn't an effect of radiations

(sorry for my english)

Answer 2

Answer: A) the Amount of Radiation

Explanation:

To create an experiment in which the objective is to determine the effects of radiation on the germination of seeds, one of the variables or determinant factors in the amount of radiation that these seeds are exposed to and see if it has any effect on the germination of seeds.