The answer is C
Completing multiple trials during an experiment
The rest of the options are possibilities of how you can "mess up" and experiment, but if you run multiple trials doing everything right, for example, making sure all variables are controlled, using the right equipment, and making sure you cover all possible variables. If you make sure you do multiple trials and you do them right, you get successful results.
So the answer is C
I hope this was helpful :)
Goodluck!!
A membrane bound nucleus (or just a nucleus in general)
Be P atient
do your O bligation
be a good L istener
being A cess to all
being R esponsible
use your I nternal feelings
use your T ongue for good
Y our officially a angel of god
the capital letters is from the word polarity