Instructions: Given a prompt and two completions from a language model, select the completion that is the most fluent with respect to continuing the prompt. Fluency is defined by coherency and ease of understanding, not necessarily grammatical correctness. Generate either Completion A or Completion B.
Input: Prompt: Thanks for small flat rate priority boxes. I'll remember to use 
Completion A: one for $20 or more.If you need to charge some extra for extra shipping, please use the promo code #HOTSTARTER 
Completion B: this
Output:
Completion B