Take a picture of me/for me (which preposition better translates)? As an experienced tourist in China, I know the sentence:你能不能给我（们）相的照吗？

Although it gives the desired result-- someone taking a picture of me, for me, with my own camera-- I am not sure of the exact corresponding English translation.

Does it mean:
A)     Can you take a picture for me?
    Or,
B)     Can you take a picture of me?

And how can I distinguish between the  two, or add a second object like "Can you take of picture of her for me?"
'给..照相' means 'take a picture of ..', so your sentence means 'can you take a picture of me'. 

The verbatim translation for 'do [something] for [someone]' is '为..做..', but in your scenario (asking stranger for help), it is more common to say '帮..做..' (help [someone] do [something]), so 'can you take a picture of her for me' would be '你能帮我给她照相吗？'