The first FRB was discovered in 2007. Essentially, FRBs are bright bursts of radio waves . Hence Statement A is Correct . Its durations lie in the millisecond-scale, because of which it is difficult to detect them and determine their position in the sky . Hence Statement B is Correct. Initially, it was believed that the collision of black holes or neutron stars triggers them. But the discovery of repeating FRBs debunked the theory of colliding objects . The source of the FRB detected in April in the Milky Way is a very powerful magnetic neutron star , referred to as a magnetar