Read the following excerpt from a US court opinion:
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United States v. Resto, 824 F.2d 210, 211-12 (2d Cir.1987) (upholding sufficiency of evidence to support defendant’s conviction for aiding sale of narcotics, including expert testimony explaining that “steerer” typically stands short distance from dealer to solicit and screen potential buyers and guide them to dealer); United States v. Cruz, 797 F.2d 90, 96 (2d Cir.1986) (sustaining admissibility of expert testimony concerning practice of exchanging food stamps for narcotics); United States v. Khan, 787 F.2d 28, 34 (2d Cir.1986) (upholding trial court’s admission of expert testimony concerning customs of narcotics dealers in Pakistan, including testimony about heroin prices and transfers of heroin with payment deferred); United States v. Daniels, 723 F.2d 31, 32-33. (8th Cir.1983) ; United States v. Pugliese, 712 F.2d 1574,
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What is the most suitable continuation to the opinion? Your options are:
A. holding admissible police officers expert testimony that narcotics dealers often use intermediary in making delivery to buyer under mistaken assumption that intermediary would insulate dealers from criminal liability
B. holding admissible expertwitness testimony that drug dealers commonly register cars and apartments in names of female friends to conceal narcotics activities
C. holding admissible police officers testimony that firearms are commonly used in drug trafficking
D. holding admissible expert testimony concerning countersurveillance techniques commonly used by narcotics dealers specifically including practice of using vehicle to observe in advance area where distribution was intended to occur
E. holding that guns were properly admitted to  prove intent to distribute drugs because it has uniformly been recognized that substantial dealers in narcotics possess firearms and that such weapons are as much tools of the trade as more commonly recognized drug paraphernalia
Reply with [A, B, C, D, E] only.