The earth is the third-largest planet in the solar system.
(State whether the sentence is true (T) or false (F).)
A. True
B. False

Hint: In order to answer this question, we will brush up some of our basic knowledge about our solar system as well as our own planet earth. We will also look upon the sizes of all the planets in the solar system.

Complete answer:
Our Earth is simply one among several Planets that revolve around our Sun, the first and central object of our system. Since the whole system, including our Earth, was created about an equivalent time (about $4.6\,billion$ years ago), our understanding of the origin and properties of the system, the Sun, and its other members are important to understand our Earth itself. We consider the dimensions of our Earth to be very large, as compared with most sizes and distances we come across in our daily lives. However, the dimensions of the world are extremely small compared to the dimensions of the system, which consists of the Sun and its family of planets, of which our Earth is merely about average in size.

Planet Sizes rank wise from biggest to smallest (radii given)
Jupiter ($69,911\,km$) – $1,120\%$ the dimensions of Earth
Saturn ($58,232\,km$) – $945\%$ the dimensions of Earth
Uranus ($25,362\,km$) – $400\%$ the dimensions of Earth
Neptune ($24,622\,km$) – $388\%$ the dimensions of Earth
Earth ($6,371\,km$)
Venus ($6,052\,km$) – $95\%$ the dimensions of Earth
Mars ($3,390\,km$) – $53\%$ the dimensions of Earth
Mercury ($2,440\,km$) – $38\%$ the dimensions of Earth
According to the data provided above, we can conclude that the Earth is the fifth largest planet in the solar system and not the third.

Hence, the correct answer is option B.

Note: It is very important to note that the Sun is not considered as a planet. The Sun is considered as a giant star and has its own luminance whereas, the planets do not have their own light and hence, are also considered as non-luminous.