Answer: 2 and 4
Explanation: Accretion can be defined as the accumulation of coastal sediment, sand or land mass on a tectonic plate at a subduction zone over time.
Planetesimals refers to the small celestial bodies of a combination of dust, rock and gas which combines to form the planets, after the solar system begin to form.
Protoplanets can be defined as a large collection of matter within a giant cloud of gas and dust in orbit around the sun and developing into a planet. Thus, a protoplanet is a large planetary embryo in its early stages of evolution through accretion.
