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". 

[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.
D