I agree with you. Those examples do not define "comes with a price".
Student or Learner
At the back of the minds of many people, especially those who miss the "good old days", efficiency comes with a price. When communication becomes more efficient, people are able to contact one another wherever they are. The click of a button allows people miles apart to talk or see each other without even leaving their homes...
Q: The author explains "efficiency comes with a price" by _____________.
The answer is by using examples.
Are the underlined parts the examples to explain " efficiency comes with a price".?
I think "efficiency comes with a price" should mean some "disadvantages" or bad results coming from efficiency. But the underlined part seems to be some positive facts coming from efficiency. Can they be counted as "a price"?
I would hope the rest of the paragraph goes on to talk about the disadvantages. Not being allowed to be left alone, or communications being more superficial because they are so easy, or something like that. Otherwise the question is impossible.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.