_______ country conducted a successful flight test of the MGTD-20 gas turbine engine made by 3D-printing for the 1st time ?

a) Russia
b) China
c) Germany
d) None of these

The Russian Foundation for Advanced Research Projects in the Defense Industry informed that Russia for the first time conducted a successful flight test of the MGTD-20 gas turbine engine made by 3D-printing. The flight tests were held at Kazalbash aviation center in Tatarstan. The production of the aircraft is scheduled on 2021-2022.