Which One of the Following Is the Best Example of Positive

Which one of the following is the best example of positive transfer?

A) When trying to write the word "shepherd," Robert remembers how he learned to spell "lighthouse" by putting two words together and so he writes "sheepherd."
B) Vince notices that rules of grammar are not always the same in English and Japanese.
C) Zelda uses the formula she learned in class for calculating the area of a circle when she wants to figure out how much bigger a 10-inch pizza is than a 7-inch pizza.
D) David is trying to learn to program a computer. He reads his programming manual but is confused by some of its instructions.