Which theory explains that the planets formed from the condensing of our sun or solar nebulae?

• A. Nebular Theory
• B. Solar Nebulae Theory
• C. Planetary Accretion Theory
• D. Geocentric Theory

Answer: (B)

Planets form from the material in a solar nebula. The Solar Nebula Theory says that a rotating cloud of gas and dust surrounding a young Sun collapsed under gravity and flattened into a disk. As the disk cooled, the dust and ice condensed into solid grains. Those grains collided and stuck together, building up into planetesimals, then protoplanets, and finally full planets. This sequence explains why planets orbit in the same general plane and why rocky planets form close to the Sun while gas giants form farther out.

Choosing the solar nebula concept specifically captures the idea that the Sun and its planets all arose from the same original nebula. A broader Nebular Theory conveys the same general origin, but the solar nebula framing emphasizes the disk around the young Sun. Geocentric theory is about Earth-centered cosmology and isn’t relevant to how planets form, and a planetary accretion view without the nebula context might miss the source material and disk environment where formation began.