Which of the following describes the benefit of using control in this experiment?
A biology student wanted to determine if using fertilizer
would promote plant growth. One hundred plants were
randomly assigned to one of two groups: one that used
the fertilizer, and one that did not use a fertilizer. Each
plant was planted in the same amount of soil and given
the same amount of water and light.
O By controlling the amount of soil, water, and light in
the experiment, we eliminate the need to have a
control group.
O By controlling the amount of soil, water, and light that
may influence the response variable, we reduce
variability in the response variable.
By controlling the amount of soil, water, and light that
may influence the response variable, we eliminate
variability in the response variable.
By controlling the amount of soil, water, and light, the
differences observed in the response variable can be
attributed to those variables that were controlled.