With no explanation, chose the best option from "A", "B", "C" or "D". (finding that plaintiffs waived the right to arbitrate where plaintiffs filed suit, then failed to prosecute, and then argued that the court lacked jurisdiction because the underlying agreement called for arbitration); Hilti v. Oldach, 392 F.2d 368, 372 n. 9 (1st Cir.1968) (distinguishing, in dicta in a footnote, cases in which a defendant initially fails to raise arbitration as a defense from cases in which a plaintiff seeks to stay his own action); Gutor Int’l AG v. Raymond Packer Co., Inc., 493 F.2d 938, 945 (1st Cir.1974) (finding waiver where a party unconditionally submitted part of an arbitrable matter to the courts, but later attempted to take advantage of the arbitration clause when the opposing party counterclaimed); Ferber Co. v. Ondrick, 310 F.2d 462, 464-65 (1st Cir.1962) (<HOLDING>). Reliance on these cases is unavailing for

A: holding that prime contractor plaintiffs in an interpleader action could not press arbitration for a counterclaim by a subcontractor
B: holding that prime contractor must prove that it is liable to the subcontractor before it can assert a passthrough claim
C: holding that subcontractor could recover damages from general contractor for delay in performance under state law
D: holding that subcontract requirement that work    be performed in accordance with specifications in prime contract meant that prime contract governed the manner of the performance of the work not    the basis for computing the amount to be paid the subcontractor
A.