Symbol for proportion is__
A.\[::\]
B.\[\cong \]
C.\[=\]
D.\[:\]

Hint: The symbol of proportion is used in mathematics for various purposes. The proportion here means the way we use a fraction.

Complete step-by-step answer:
Proportion says that two ratios (or fractions) are equal. Example: 1/3 = 2/6. See: Equivalent Fractions.
The symbol \[::\] means ‘as to’. We write \[x::y\] which means \[x\] is proportional to \[y\] or \[x\] as to \[y\].
The symbol \[\cong \] stands for approximately equal. Any answer which is very long or which is difficult to simplify but we know that the answer will be approximately equal to some other value we know then we use this sign to depict an answer. This is also used when the answer comes in big decimal answers and we need to shorten the answer.
The symbol \[=\] stands for equals to.
The symbol \[:\] stands for ‘is to’.
The correct answer to this question will be option A. \[::\]. The symbol for proportion is \[::\].
So, the correct answer is “Option A”.

Note: The symbols \[=\] and \[:\] can be used in many similar places where we want to signify an answer or where we want to show some parameters value and many other uses.