Please remember that "to be" is sometimes a linking verb: English is the international language. All languages are important. This website is popular. And sometimes "to be" is a verb that means something like "to exist." He is in the cafeteria. The books are on the table. If it rains hard, inside the house is the safest place to be. Remember what Shakespeare said: "To be, or not to be: that is the question." (To exist [live], or not to exist: that is the question.)

Your sentence is incorrect. I'm guessing it should read 'It is the safest place to be'. This sentence means that the place the person is talking about (The person would of either specified the place before he said this sentence or would be pointing at a place) is the safest place out of all places to be.

To be a teacher or a doctor is the question to answer.