Hi!
Your answer is C.
A is an example because it's not good to only make identify one solution; you need backups or a variety of ways.
B is an example because, hey, not everything is true! Especially on the internet. Questioning source information is great because then you are sure what you are seeing is unbiased and accurate.
C is NOT an example. As stated above, you need a variety of solutions, but you can't just pick the first solution; you want to pick the <em>best</em> solution for the problem at hand.
D is an example. As stated above, questioning source information is great, but then you need to also verify it, because, like said before, not everything is true.