Im relatively new to Python, and I was wondering if I could get a fresh set of eyes. I have been coding a simple if/elif structure, with not !=, or conditionals inside. My goal is for it to iterate through each item in the list, determine whether or not the item is equal to one of three specified string values, and produce an error if it is not. I am not entirely sure why this code doesn't execute properly, but I would greatly appreciate any help you're willing to give!

```
if yes_or_no_further_data.lower() == 'yes' or yes_or_no_further_data.lower() =='y':
        #The following code asks the user what further information they would like to specify, and possible calculations that could be derived from this
        print('\nPlease select the letter(s) of the following information you would like to enter, spaced out: \n')
        print('\tA) Precise byproducts from the Nuclear Reaction (gives more precise energy output) \n')
        print('\tB) The total amount of energy lost \n')
        print('\tC) What your specified amount of energy could potentially power \n')

        userwish = input()
        ightybro = userwish.strip(',').split()

        for i in ightybro:
            if i.lower() != 'a' or i.lower() != 'b' or i.lower() != 'c':
                print(i)
                print('An error occurred, you entered an incorrect letter! Please enter the letter(s) A, B, or C (you can also enter multiple)')
                userwish = input()
                ightybro = userwish.strip().split()
                if i.lower() == 'a' or i.lower() == 'b' or i.lower() == 'c':
                    break
            else:
                continue

```

I am not entirely sure why the != "if" structure does not execute properly. When I enter "a b c" into my console, the program still goes through the if structure, despite each value equaling one of the three specified values.

Thanks in advance!