Step 1: Understanding frustration.
Frustration occurs when performance becomes impossible due to events beyond control. Section 65 ensures that benefits received are restored when a contract becomes void.
Step 2: Eliminate incorrect answers.
(a) Breach is different — it is a voluntary failure to perform.
(b) Frustration is not due to a party’s own act.
(c) Misworded — "adjusted" is more accurate than "existed."
(d) Correct — Section 65 adjusts parties’ rights after frustration.
\[
\boxed{(d)}
\]