The inner planets refer to the four planets in our solar system that are closest to the Sun: Mercury, Venus, Earth, and Mars. These planets are located between the Sun and the Asteroid Belt, which is why the correct answer is option 'B' - Sun and the Asteroid Belt.

Below is a detailed explanation of the answer:

1. Inner Planets:
The inner planets, also known as terrestrial planets, are the four planets closest to the Sun. They are primarily composed of rock and metal, unlike the outer planets which are mostly gas giants. The inner planets are:

- Mercury: It is the closest planet to the Sun and has a rocky surface with extreme temperatures.
- Venus: It is the second planet from the Sun and is known for its thick atmosphere and high surface temperatures.
- Earth: Our home planet, Earth, is the third planet from the Sun and is unique with its abundant liquid water and life-supporting conditions.
- Mars: It is the fourth planet from the Sun and is often referred to as the "Red Planet" due to its reddish appearance. Mars has a thin atmosphere and is being explored for potential signs of past or present life.

2. Sun:
The Sun is the central star of our solar system. It is a massive ball of hot, glowing gas that provides heat and light to the planets and other celestial bodies in its gravitational pull. The Sun's immense gravitational force holds the inner planets in their orbits around it.

3. Asteroid Belt:
The Asteroid Belt is a region of space located between the orbits of Mars and Jupiter. It is primarily composed of numerous rocky and metallic objects called asteroids. These asteroids vary in size, from small rocky fragments to large bodies several hundred kilometers in diameter. The Asteroid Belt is often described as a "belt" because it contains numerous asteroids, but it is not a dense or continuous ring of objects.

4. Location of Inner Planets:
The inner planets, Mercury, Venus, Earth, and Mars, are located between the Sun and the Asteroid Belt. They orbit the Sun relatively close compared to the outer planets, and their orbits are not disturbed by the gravitational influence of Jupiter and other gas giants.

Therefore, the correct answer is option 'B' - Sun and the Asteroid Belt, as it accurately describes the location of the inner planets in our solar system.