Instruction: Rank items in listed options based on the user's purchase history to determine the item that the user is most likely to purchase next. Output the item with the highest likelihood of being the next purchase.

Input:
1st: Nikon SB-900 AF Speedlight Flash for Nikon Digital SLR Cameras . Electronics. Camera & Photo. Nikon.
2nd: Nikon 18-55mm f/3.5-5.6G AF-S DX VR Nikkor Zoom Lens - White Box (New) (Bulk Packaging). Electronics. Camera & Photo. Nikon.
3rd: 3.5mm Headset - iKross In-Ear 3.5mm Noise-Isolation Stereo Earbuds Headphones with Microphone - Metallic Red/Black. Electronics. Headphones. iKross.
4th: Sigma 70-300mm f/4-5.6 DG Macro Telephoto Zoom Lens for Canon SLR Cameras. Electronics. Camera & Photo. Sigma.
5th: Neewer 43-inch / 110cm 5-in-1 Collapsible Multi-Disc Light Reflector with Bag - Translucent, Silver, Gold, White and Black. Electronics. Camera & Photo. Neewer.
6th: PTC 10 ft Premium VGA / SVGA / UXGA Monitor or Projector w/ AUDIO Cable - UL Listed Double Shielded Coaxial Type to Support Extra...
7th: Dynamo-On-the-Go 5600mAh External Battery Pack Power Bank  with  Built-in Flashlight, Free Wall Charger and Carrying Pouch. Electronics. Portable Audio & Video. RAVPower.

Options:
A: Dash kit and Wire Harness for Installing a New Single Din Radio into a Jeep Grand Cherokee 1993-1998 and a Dodge Avenger 1995-2000. Electronics. Car...
B: Carson C6 Series Lens Cleaners for Cleaning Scopes, Binoculars, Cameras and Optics. Electronics. Camera & Photo. Carson.
C: Thermarest Camper Deluxe 5.0 Self Inflating Sleeping Pad. Sports & Outdoors. Outdoor Recreation. Therm-a-Rest.
D: Power Bright PW6000-12 Power Inverter 6000 Watt 12 Volt DC To 110 Volt AC. Electronics. Accessories & Supplies. PowerBright.
E: DELL INSPIRON 15R 5520 REPLACEMENT LAPTOP 15.6" LCD LED Display Screen. Electronics. Computers & Accessories. Dell.
F: Sennheiser  EH2200 Professional HiFi Studio Headphones. Electronics. Headphones. Sennheiser.
G: Present Time Ice Cooler with Tin Scoop, White. Home & Kitchen. Kitchen & Dining. Present Time.
H: Apple Mac Mini MC936LL/A with Lion Server (OLD VERSION). Electronics. Computers & Accessories. Apple.
I: Therasage Ps2002 Portable Far Infrared Sauna, Black, Large. Sports & Outdoors. Sports & Fitness. Therasage.
J: Zomei 37MM Professional Camera CPL Circular Polarizer, Fader ND Variable Neutral Density with Clip for iPhone 6S, 6S Plus, Samsung Galaxy, and Android Smartphones. Electronics...
K: Commercial swing hanger galvanized to attach to wood beam. Home & Kitchen. Storage & Organization. Playkids.
L: Fin-Finder Heavy Duty Drum Reel, Blue. Sports & Outdoors. Sports & Fitness. Fin-Finder.
M: MONARCH TV STAND - 48"L/WHITE. Home & Kitchen. Furniture. Monarch Specialties.
N: Brentwood KT-1618, 10.20in. x 9.00in. x 6.00in, Black. Home & Kitchen. Kitchen & Dining. Brentwood.
O: Winco White 100 Percent Cotton Bar Towel, 16 x 19 inch - 12 per case. Home & Kitchen. Kitchen & Dining. Winco.
P: Belkin Ultra Slim Aluminium Series 4-Port USB 2.0 Hub (F4U038-APL). Electronics. Computers & Accessories. Belkin.
Q: Mark Mender Golf Divot Repair Tool & Cigar Holder. Sports & Outdoors. Sports & Fitness. Mark Mender.
R: BestDealUSA 3.5mm Male to Male Stereo Audio Extension Cable Aux. Electronics. Accessories & Supplies. BestDealUSA.
S: Schwinn Alloy Bicycle Water Bottle Cage . Sports & Outdoors. Outdoor Recreation. Schwinn.
T: (New Arrival) TaoTronics TT-CD03 2.7-inch TFT LCD Car Dash Cam DVR Vehicle Accident Video Camera Recorder Rear View Mirror Type with 120-Deg. Wide Viewing Angle,...
Answer: R