Neutron stars, smaller than white dwarfs, are thought to be remnants of a. supernova events b. black holes c. nucleosynthesis d. red giants

Its supernova events

The correct answer is option A, Supernova even

Explanation:

Neutron star is the remnants of Supernova event. A supernova remnant includes the remains of the atmosphere of the massive supernova star after the event of explosion. The shock waves produced by the explosion passed though the interstellar medium thereby densifying it to the level where a new star can be produced. The neutron star formed in this way is basically a highly dense mass of neutrons.

answer: land bridge theory. land bridge theory held that shifting portions of dry land explained the finding of identical species on different continents. plate tectonic theory eventually eliminated the land bridge theory.