Question

Fusion is the process by which

A) dust grains and ice crystals coalesce to form planetesimals.
B) massive protoplanetary cores pull gas onto themselves to create giant planets.
C) clouds of interstellar gas and dust contract to form protostars.
D) elements are transformed into heavier elements by nuclear reactions.

Answer 1

Option D) is the correct answer. Fusion is a process occurring in stars where elements are combined to form heavier elements through nuclear reactions, releasing energy and contributing to the creation of new cosmic materials.

Step-by-step explanation:

Fusion is the process by which elements are transformed into heavier elements by nuclear reactions. This fundamental process powers stars, including our sun. Within the dense cores of stars, hydrogen atoms merge to form helium through nuclear fusion, releasing a vast amount of energy in the process. As stars evolve, they can fuse heavier elements until iron is formed, beyond which energy input is required to fuse elements. In the cosmos, the fusion of elements in stars leads to the complex array of elements we see. Additionally, during the violent death of stars, such as in a supernova, new elements are created and scattered throughout space, contributing to the cosmic material from which new stars and planetary systems may arise.