The value of $ {(21)^0} $ is –

Hint: : In order to solve the given question , we should know the important concepts related to the question that is exponents . An exponential number is a function that is expressed in the form $ {x^a} $ , where $ x $ represents a constant, known as the base, and ‘ $ a $ ’, the exponent of this function, and can be any number. The exponent of a number says how many times the base is multiplied to itself . Exponents can also be called as Power. For example = $ {5^2} $ could be called “ $ 5 $ to the power “ $ 2 $ ” that means the “ $ 2 $ ” says to use $ 5 $ twice in a multiplication. So, 5 is the base and 2 is the power . For an instance , $ {5^2} = 5 \times 5 = 25 $ . To simplify this question , we need to solve it and verify it step by step .

Complete step-by-step answer:
The number $ {(21)^0} $ is an exponential term where $ 21 $ represents a constant, known as the base, and ‘ $ 0 $ ’, the exponent.
But since we know that multiplication of one and any exponential number is equivalent to the exponential number itself.
 $ \Rightarrow {(21)^0} = 1 \times {21^0} = 1 \times 1 $
 Now, we write the number 1 and the base number 21 zero times.
 $ \Rightarrow {(21)^0} = 1 $
Therefore, it is proven that any number or expression raised to the power of zero is always equal to 1. In other words, if the exponent is zero then the result is 1. The general form of zero exponent rule is given by: \[{\text{ }}a{\;^0}\; = {\text{ }}1{\text{ }}and{\text{ }}{\left( {\dfrac{a}{b}} \right)^0}\;\; = {\text{ }}1.\]This is also known as the Zero Exponent Rule .
Therefore, the value of $ {(21)^0} = 1 $
So, the correct answer is 1.

Note: Always remember you can perform calculations only between like terms .
Always try to work on the positive exponents .
The expression is having hidden multiplication when written altogether .
Always check the required formula exponent rule .
Do not forget to verify the exponents solved correctly .
Always try to cancel out the similar terms for the solution of simplification
Any number or expression raised to the power of zero is always equal to 1.