With no explanation, chose the best option from "A", "B", "C" or "D". of the balancing test first articulated in Lear. See, e.g., Warner-Jenkinson Co. v. Allied Chem. Corp., 567 F.2d 184, 187-88 (2d Cir.1977) (licensee could litigate the validity of patent even though licensing agreement was entered into as part of a settlement-of earlier litigation); Schlegel Mfg. Co. v. U.S.M. Corp., 525 F.2d 775, 781 (6th Cir.1975) (enforcing consent decree, which recited that plaintiffs patent was valid); Kraly v. Nat’l Distillers & Chem. Corp., 502 F.2d 1366, 1369 (7th Cir.1974) (concluding that a licensee was not es-topped from challenging the validity of a patent even where a consent decree incorporated an understanding that the patent would not be challenged); Massillon-Cleveland-Akron Sign Co. v. Golden State Adver. Co., 444 F.2d 425, 427 (9th Cir. 1971) (<HOLDING>). The Lear balancing test has also been

A: holding employment agreement consisting entirely of a covenant not to compete unenforceable because the covenant must be supported by valuable consideration
B: holding that a restrictive covenant with a tenyear term was unenforceable
C: holding that a settlement agreement in which the parties failed to agree upon the terms of a release was unenforceable
D: holding that covenant in settlement agreement whereby defendants agreed not to contest validity of patent was unenforceable because in direct conflict with strong federal policy
D.