With no explanation, chose the best option from "A", "B", "C" or "D". disclaim or disavow the broad scope of a claim, one should not draw limitations into the claim from a preferred embodiment. See Phillips, 415 F.3d at 1323 (“[w]e have expressly rejected the contention that if a patent describes only a single embodiment, the claims of the patent must be construed as being limited to that embodiment”). However, Curtiss-Wright’s argument is unavailing, because the requirement that the live loaded seat be “adjustable” is an express limitation of the claim. It is permissible to refer to the specification for the purposes of construing the meaning of an express limitation in a claim. See Phillips, 415 F.3d at 1315-16 (“The specification is, thus, the primary basis for construing the claims.”); Terlep v. Brinkmann, 418 F.3d 1379, 1384 (Fed.Cir.2005) (<HOLDING>); Merck & Co. v. Teva Pharms. USA, Inc., 395

A: holding that although term was not limited by the specification it was expressly defined in a narrow manner in the prosecution history
B: recognizing that it was proper for the district court to assign meaning to a term by reference to the specification and that this was not an impermissible importation of a functional limitation
C: holding improper reading into claims a limitation appearing only in the specification
D: recognizing that plain meaning does not control where context shows that the parties have assigned an unusual meaning to a term
B.