Read the following excerpt from a US court opinion:
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v. Greenway, 170 Ariz. 155, 167-68, 823 P.2d 22, 34-35 (1991) (rejecting double jeopardy argument and finding aggravating factor applied to each of defendant’s first degree murder convictions when both murders were committed during commission of offense); see also State v. Ramirez, 178 Ariz. 116, 131, 871 P.2d 237, 252 (1994) (same). 9. Is the death penalty proportional in this case? See State v. Salazar, 173 Ariz. 399, 417, 844 P.2d 566, 584 (1992) (proportionality review not constitutionally required and court no longer conducts them). 10. Is death by lethal gas cruel and unusual punishment, barred by the 8th and 14th Amendments to the United States Constitution and article 2, § 15 of the Arizona Constitution? No. State v. Williams, 166 Ariz. 132, 142, 800 P.2d 1240, 1250 (1987) ; see also Ariz. Const, art. 22, § 22 (approved
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What is the most suitable continuation to the opinion? Your options are:
A. holding that execution of the mentally retarded is prohibited under the eighth amendment to the united states constitution
B. holding that defendants claim that execution by electrocution or lethal injection constitutes cruel and unusual punishment is meritless
C. holding execution of mentally retarded individuals fails to achieve legitimate penalogical objectives for punishment as required by the eighth amendment to the united states constitution and article i  16 of the tennessee constitution
D. holding that execution by lethal gas is not cruel and unusual punishment prohibited by either 8th and 14th amendments to united states constitution or article 2  15 of the arizona constitution
E. holding californias sole method of execution lethal gas unconstitutional under the federal cruel and unusual provision
Reply with [A, B, C, D, E] only.