Final answer:
The main characteristics of our solar system include a central Sun, four small rocky terrestrial planets near the Sun, followed by four large gaseous giant planets farther out. The correct description of this structure is reflected in option A. The solar system also contains dwarf planets, moons, asteroids, and comets.
Step-by-step explanation:
The main characteristics of our solar system include a variety of components that orbit the Sun. These objects, ranging from planets to smaller debris like comets and asteroids, formed from the same primordial gas and dust cloud approximately 4.5 billion years ago.
Characteristic A describes our solar system accurately, with four small inner planets, known as terrestrial planets, comprised mainly of rock and metal. These planets are Mercury, Venus, Earth, and Mars. Outside of these lie the four giant planets, which are significantly larger and mostly gaseous.
These outer giants, specifically Jupiter, Saturn, Uranus, and Neptune, are recognized for their size and composition, which sets them apart from the rocky inner planets. The dwarf planet Pluto, along with other objects such as moons and asteroid belts, is categorized separately and will be discussed further in advanced topics related to the solar system.