Can somebody please explain this.
This sentence is in subjunctive mood, since the imposter is not really a licensed practitioner, but is just trying to fake it. So it is a hypothetical scenario.
In case of subjunctive mood were
is used instead of was
. Just remember these famous lines from Tim Hardin's songIf I were a carpenter, and you were a lady
Would you marry me anyway?
Would you have my baby?
Now in this question only option A
correctly portrays the subjunctive mood, but in case there were 2 options as below
-- as though she were a licensed practitioner
-- as if she were a licensed practitioner
Then it would have been tough to select the correct answer, as grammatically both are correct and imply the same meaning.
There is a very subtle difference between "as if" and "as though", "as if" is used to refer to a less likely scenario. For e.g.
1.) You are so scared of him as if
he is going to eat you.
2.) You are so scared of him as though
he is going to hit you.
Now you could also use "as if" in the 2nd sentence but given a choice "as though" would be more suitable.
Coming back to the original sentence, the imposter could have easily been a licensed practitioner, it's not like she behaved as if she were a dragon
Life is a highway
I wanna ride it all night long