Is the process of adding atoms to the center of a protostar or gravitational center in space.

a) accretion
b) photosynthesis
c) equilibrium
d) nuclear fusion

A) Accretion

Explanation:-

Accretion is the accumulation of particles into a large object caused by gravitation.Most galaxies, stars, and planets are formed by accretion process.

Photosynthesis is a phenomenon in which green plants containing chlorophyll use sunlight as a source of energy to convert carbon dioxide and water to form glucose and oxygen.

Equilibrium is a reversible chemical reaction in which rate of forward reaction is equal to the rate of backward reaction. The concentration of the reactants and products remain constant.

Nuclear fusion is a process which involves the conversion of two small nuclei to form a heavy nuclei along with release of energy.

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