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!!
Syntax is also collectively known the arrangement of words in a sentence. The correct answer to your questino is B. For that reason it isn't possible for any other answer in this case to be correct because B actually denotes a rather formal way of how you could talk about syntax.
Carlos Linnaeus is considered as the "Father of morden Txonomy."