A. True
Una músico es una persona que toca un instrumento
means
A musician is a person who plays an instrument
this is true
Estas oficinas! Is plural
The most known Christopher Columbus statue is located in Barcelona (Spain). It's a 60m height monument. But you can find a statue of Him in Brooklyn N.Y. (U.S.), in santo domingo (Capital of Dominican Republic), etc...
The Picture below represents the Columbus Monument in Barcelona, Spain.
Hope this Helps! :)