Read the following article and select the best answer. Article: We humans can play the piano . of course we play the piano with our ten fingers . But Teotronica can play with its 19 fingers . Teotronica is not a human . It is a robot . It is a special robot which can play the piano like humans . Nattei Suzzi is the inventor of Teotronica . Matteo Suzzi comes from Italy and he is more than thirty years old . He was interested in science when he was young . He always likes to use his head to create amazing things . He spent four years making the musical robot . He made the piano-playing robot at a cost of about 4,700 dollars . Teotronica is a special and great robot . It has more fingers than humans . It plays the piano faster than a human . Teotronica can sing as well when it plays the piano . It is the first robot to do so and many people feel excited to see it ,. Teotronica can even use its eyes to interact with humans because there are cameras in its eyes .Teotronica is amazing , isn't it ? Question: How long did it take Matteo Suzzi to make Teotronica ? - Two years . - Three years . - Five years . - Four years .
The answer to this question is:
Four years .