Which of These Exoplanet Characteristics Is MOST Difficult to Explain

question 66

Multiple Choice

Which of these exoplanet characteristics is MOST difficult to explain with the Nice model of planetary system formation?

• A) Exoplanets that orbit in an opposite direction from their star's rotation.
• B) Gas giants with orbits smaller than Mercury.
• C) The relative proportion of gas giant and terrestrial planets in exoplanet systems.
• D) The existence of free-floating planets.

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Definitions:

Primary Germ Layers

The three initial layers of cells (ectoderm, mesoderm, and endoderm) in the early embryo from which all bodily tissues and organs develop.

Digestive Organs

Organs involved in the digestion process, including the mouth, esophagus, stomach, liver, gallbladder, pancreas, intestines, rectum, and anus.

Respiratory Organs

Organs involved in the process of breathing, including the nose, throat, larynx, trachea, bronchi, and lungs.

Extraembryonic Membrane

Membranes that support the development of the embryo, such as the amnion and chorion.