In the universe, what are pulsars?

Correct answer: (b) Rotating neutron stars

Explanation

Pulsars are highly dense, rapidly rotating neutron stars that emit beams of electromagnetic radiation.

They act like cosmic lighthouses, sending out regular pulses of radio waves, X-rays and gamma rays, and form after a supernova collapse.

They are single rotating stars, not a star group, an explosion, or merely radio waves.