Q: 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 make a dynamo easily [title] Find a small hobby motor, those ones with some sort of wheel on the shaft. [title] Mount the motor on like a board or block of wood. [title] Find another bigger wheel and mount it on a pin or something on the same block of wood. <sep> (A) [step] This does not have to be the one that looks like the motor. [title] Choose one brand of motor for speed and keep one brand for durability. (B) [title] Put a handle on the bigger wheel. [title] Then get a rubber band and put it around the two wheels and start turning the handle. (C) [step] Be sure it is at least 2 to 4 " x6 " so when you get back to the original one at your place you are not left with 3 sided wheels which would cost more money. [title] Put the current motor on top of the new one. (D) [title] Put fuel on it for the motor and drive around. [title] Be careful as this is a rock and any force you make will result in a fuel flame/spark.
A:
B