PT 36 S3 Q26

Before 1986 physicists believed they could describe the universe in terms ... ...

Which one of the following, if true, most strengthens the argument that there is a fifth universal force?
(A) The extremely sophisticated equipment used for the experiments was not available to physicists before the 1970s
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in Practice Set: "Stronger" Questions, Set 3 - Difficult/Uncommon Mix (25Q)