The procedure for an experiment
a.) the variable that you will change
b.) a set of safety rules that you need to follow in the lab
c.) what you’re going to do and how you’re going to do it
d.) research you’ve done about the topic you’re investigating

Clarification:

I believe that you're looking for what an experiment is, or how to make one, rather than its steps. If you were to look for its steps, the options would be different.

Elimination:

An experiment isn't a variable you'll change - A is incorrect.

An experiment isn't a set of lab rules - B is incorrect.

An experiment isn't the same thing as a research - D is incorrect.

An experiment is a procedure where you look for proof and evidence for your research. For this you will need to know how and what to do. - C is correct.

Hope it helped,

BiologiaMagister

children tend to take more after their grandparents more than their parents. it’s the dna you received that was passed down to you somewhere in your family. maybe one of your grandparents had/has straight hair and you might have gotten it from them.

for  example, forests have higher evapotranspiration than other ecosystems,  such  as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.