Let's break down each option in List A and match it with the appropriate option in List B.
I. A, B are mutually exclusive events:
For mutually exclusive events, the occurrence of one event excludes the occurrence of the other event. Thus, the probability of their union is simply the sum of the probabilities of the individual events:
\[
P(A \cup B) = P(A) + P(B).
\]
So, the correct match for this is (IV) from List B.
II. A, B are independent events:
For independent events, the occurrence of one event does not affect the occurrence of the other. The probability of the intersection of two independent events is the product of their individual probabilities:
\[
P(A \cap B) = P(A)P(B).
\]
Thus, the correct match for this is (d) from List B.
III. A \cap B = A:
If \( A \cap B = A \), this means that event \( A \) completely occurs within event \( B \). In such cases, the probability of \( A \cup B \) will simply be the probability of \( B \):
\[
P(A \cup B) = P(B).
\]
So, the correct match for this is (c) from List B.
IV. A \cup B = S:
If \( A \cup B = S \), this means that the union of events \( A \) and \( B \) covers the entire sample space. The probability of their union would be 1:
\[
P(A \cup B) = 1.
\]
Thus, the correct match for this is (a) from List B.
### Final Answer:
- I matches with (d) from List B.
- II matches with (c) from List B.
- III matches with (b) from List B.
- IV matches with (a) from List B.
Thus, the correct match is:
\[
\boxed{I - d, II - c, III - b, IV - a}.
\]