This is a Sufficient Assumption question so our job is to add a premise to make the existing argument valid.
It's a very difficult question because you had to realize that they fed you the definition of "prudent" in the premises. The definition is "forming opinions of others only after cautiously gathering and weighing the evidence."
If you can't get over that hurdle, you're likely getting this question wrong.
Assuming you made that connection, then replace that long definition in the premises with the word "prudent" and you should see that this is like any other SA question.
Premise in English: being prudent will make people resent you.
Premise in Lawgic: P --> R
Conclusion in English: appearing prudent is imprudent
Conclusion in Lawgic: P --> Imp
What's the missing SA?
SA in Lawgic: R --> Imp
SA in English: making people resent you is imprudent.
That's (E)