Read the following excerpt from a US court opinion:
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discharge claim. 2. The district court did not err by granting summary judgment to Caldwell on Sorenson’s retaliatory discharge claim, because he did not raise a triable issue of fact regarding a causal link between his involvement in a protected activity and an adverse employment action. See Brooks v. City of San Mateo, 229 F.3d 917, 928 (9th Cir. 2000) (concluding a plaintiff must show the following for a prima facie case of retaliation: “(1) involvement in a protected activity, (2) an adverse employment action and (3) a causal link between the two”). Sorenson did not allege facts showing that his age-discrimination complaint was a but-for cause of any adverse employment action. See Univ. of Tex. Sw. Med. Ctr. v. Nassar, — U.S. -, 133 S.Ct. 2517, 2534, 186 L.Ed.2d 503 (2013) ; Hard-age v. CBS Broad. Inc., 427 F.3d 1177,
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What is the most suitable continuation to the opinion? Your options are:
A. holding the third element of the test requires a plaintiff to show that his or her protected activity was a butfor cause of the alleged adverse action by the employer
B. holding in the title vii context that the plaintiff must show that the individual who took adverse action against him know of the employees plaintiffs protected activity
C. holding that the plaintiff had to provide direct or circumstantial evidence that the supervisors who took the adverse action against the plaintiff knew about the protected activity prior to taking that action
D. holding that to establish a causal connection plaintiff must show that the individual who took adverse action against him knew of the employees protected activity
E. holding that although evidence that the alleged adverse action occurred shortly after the employer became aware of the protected activity is sufficient to make a prima facie causation case the opposite is equally true  a lengthy time lapse between the employer becoming aware of the protected activity and the alleged adverse employment action  negates any inference that a causal connection exists between the two
Reply with [A, B, C, D, E] only.