Choose True/ False for the following statement.
All rectangles are square.
A.True
B.False

Hint- In order to solve this problem use the definition and properties of both squares and rectangle. Conclude the answer as true if all the properties of square are found in rectangle and conclude false if all the properties of square are not found in rectangle.

Complete step-by-step answer:
Let us first see the definition of both the figures
Definition of rectangle
A quadrilateral is a rectangle if all four internal angles are ${90^0}$
Definition of square
A quadrilateral is a square if all four internal angles ${90^0}$ are and all four sides are equal in measure.
Note that the first condition for a square is the same as the only condition for a rectangle, and thus all squares are rectangles. However, there is no condition which requires a rectangle to have four equal sides, and thus not all rectangles are squares.
For the example:


The above is a rectangle, as all four angles are ${90^0}$, but is not a square, as the two vertical sides are shorter than the two horizontal sides.
Hence, all rectangles are not square.
So, option B is the correct option and the statement is false.

Note- Square is a special kind of rectangle, it is one where all the sides have the same length. Thus every square is a rectangle because it is a quadrilateral with all four angles right angles. However not every rectangle is a square, to be a square its sides must have the same length. Students may directly solve these types of problems by visualization of figures.