In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D". 

[EX Q]: A dog is outside in a large field and runs towards a man holding a yellow frisbee. the man <sep> (A) then throws the frisbee, the dog catches it and begins swimming back and forth in the water. (B) frisbee the dog around the frisbee and the dog chases the frisbee and catches the frisbees. (C) attempts to catch the frisbee but it is deflected by the large dog. (D) then begins walking and throws the frisbee for the dog to catch.
[EX A]: D

[EX Q]: A man demonstrates how to walk across and navigate a slackline in a grass courtyard in front of apartments. the man <sep> (A) demonstrates how to traverse a low brick fence on a residential street. (B) walks slowly across the slackline while talking and stopping to talk to passerbys. (C) stands on a slackline balancing himself with his arms before the clip cuts to him interviewing. (D) poles backward, glasses on and he begins to walk while holding the slackline while walking across the courtyard.
[EX A]: C

[EX Q]: [header] How to measure mass [title] Know that f (force) = m (mass) * a (acceleration). [step] This simple equation is what you'll use to convert weight into mass (or mass into weight, if you want to). Don't be worried about what the letters mean-we'll tell you : [substeps] Force is the same thing as weight. <sep> (A) Co (force) is the same thing as mass. N (force) is another thing to consider. (B) We convert this to mass with the same exponent in pounds. [title] Measure weight in ounces before eating junk food. (C) We will stand in a crowded elevator and say to ourselves " m (force) + u * u. r = r (( acceleration) + u "] or " l " again if you want to math and multiply mass by mass. (D) Use newtons (n) as weight. Mass is what you're solving for, so it may not be defined to begin with.
[EX A]:
D