Nelson's hobby is tinkering with small appliances.
Tinkering with implies that Nelson is unskilled at his hobby. You want to change the flavor of this sentence to show that Nelson is, in fact, quite skilled at his hobby. Which of the following should you choose to replace tinkering with so that the reader gets the right idea?
A. Selling
B. Fiddling with
C. Repairing
D. Messing with