What is the definition of certainty according to the text?

Certainty is a psychological state that gives absolute security to an opinion because it harbors no doubt about its validity.
Certainty is a psychological state that gives partial security to an opinion because it harbors some doubt about its validity.
Certainty is a psychological state that gives no security to an opinion because it harbors doubt about its validity.
a) Certainty is a psychological state that gives absolute security to an opinion because it harbors no doubt about its validity.
b) Certainty is a psychological state that gives partial security to an opinion because it harbors some doubt about its validity.
c) Certainty is a psychological state that gives no security to an opinion because it harbors doubt about its validity.