Chose the right answer
One day, Percy Spencer walked by a magnetron with a candy bar in his pocket, and it melted. It was the late 1940's and soon after, in 1947, a new kitchen appliance was created. They were large and expensive, but with the main advantage of speed. This invention has shaped how people cook and warm food even today.
A.
How Percy Spencer accidentally invented the microwave.
B.
The process in which a candy bar can be melted by a microwave.
C.
The original size and cost of the original microwave.
D.
The way microwaves have changed since it was invented.