(1) A witness shall answer all questions legal and pertinent to the matter in issue, although an answer may establish a claim against the witness.
(2) A witness need not give an answer which will subject him to punishment for a felony.
(3) A witness need not give an answer which will degrade his character, unless it is to the very fact in issue or to a fact from which the fact in issue would be presumed.
(4) A witness must answer as to the fact of any previous conviction of a felony.