(d) It is proposed to prove a fact (A) which is said to have been the cause or effect of fact in issue. There are several intermediate facts (B, C and D) which must be shown to exist before the fact (a) can be regarded as the cause or effect of the fact in issue. The Court may either permit A to be proved before B, C or D is proved, or may require proof of B, C and D before permitting proof of A.