With no explanation, chose the best option from "A", "B", "C" or "D". v. Charles, 213 F.3d 10, 24 (1st Cir.2000); United States v. Martinez, 144 F.3d 189, 190 (1st Cir.1998). In this Circuit, the types of evidence relied upon by district courts to determine that a particular substance is crack cocaine under the Guidelines include: (1) a chemist’s testimony that the substance was cocaine base, combined with an investigator’s testimony that the substance was crack, and the defendant’s own admission that he sold “rock,” see Robinson, 144 F.3d at 109; (2) a chemist’s testimony that the substance was cocaine base and that sodium bicarbonate (usually used in processing crack cocaine) was present, together with the testimony of three different law enforcement agents that the substance was crack, see Richardson, 225 F.3d at 50. Accord Martinez, 144 F.3d at 190 (<HOLDING>) id.; see also Charles, 213 F.3d at 24-25

A: holding that the term cocaine base in 21 usc  841b1 refers to cocaine in its chemically basic form which includes but is not limited to crack cocaine
B: holding that sentencing disparity between crack and powder cocaine is constitutional
C: holding that district court did not err in determining that cocaine base was crack cocaine based on chemical analysis identifying cocaine base together with competent lay testimony bridging the evidentiary gap between cocaine base and crack cocaine and refusing to require showing of smokeability ie water solubility or melting point for purposes of establishing crack cocaine under the guidelines since smokeability distinguishes cocaine base from powder cocaine not from crack
D: holding that the evidence was sufficient to support a conviction under  856 where premises contained two white envelopes containing thirtytwo packs of crack cocaine equipment required for the manufacture and packaging of crack cocaine fortyone white envelopes containing particles of crack cocaine and crack cocaine stored in a laundry bag in the bathroom
C.