If symbol denotes one arithmetic operation what is the value

zozo123 wrote:If # denotes one of the four arithmetic operations addition, subtraction, multiplication and division, what is the value of 1 # 2?

(1) n # 0 = n for all integers n

=> n # 0 = n can be : n - 0 = n OR n + 0 = n then # can be + or -

(2) n # n = 0 for all integers n

=> n - n = 0 : ok
=> n + n = 0 :nok
=> n * n = 0 :nok
=> n / n = 0 :nok

mendiratta wrote:
In 2) - what if n = 0 (because it says for all integers n)?
=> n - n = 0 : ok
=> n + n = 0 :ok
=> n * n = 0 :ok
=> n / n = 0 :nok

so we can't tell what is the function "#".

is there anything wrong in above explanation because I think answer should be E.