When you use the word “basically”, you are saying that there are details that you could go into, but which you are sparing from your audience to keep things simple for them. When students use it in exams, however, it more often than not means “I don’t know the facts” or “I don’t know how to express myself.” Don’t use it.
In general, efficiency is a measure of some sort of return on investment. Cost-efficiency is how much you get for your money. Fuel efficiency is how much you get per litre of petrol. Time efficiency is how much you get per hour. On its own, though, efficiency doesn’t mean anything much. Don’t use it without clarifying what type of efficiency you are talking about.
In terms of
This phrase is used when the author wants to associate two concepts but either hasn’t got the vocabulary to do it or just wants to sound wordy. It is lazy and if you use it incorrectly it can earmark you as a weak candidate. It’s almost always better to use “in relation to” or just to eliminate it altogether, as in the sentence “In terms of cost, leased lines are expensive.”
Putting things “in quotes”
It’s very unlikely that you will be quoting someone in a computer science exam so my advice would be don’t put anything quotes. You are either being too informal or you are highlighting your inability to express yourself appropriately. Find another way of saying it.