Which sentence should I use when I pass the exam? I mean at the time of announcing the result.
a) I cleared the Exam. (Past Tense)
It refers to the past event of passing the exam. I mean results were declared first and then I am announcing to my family.
b) I clear the Exam (Present Tense)
It refers to the current status of passing the exam.
c ) I have cleared the Exam (Present Perfect Tense)
I think this is the correct sentence to be used because it is referring to a past event having an impact on the present.