I have such a question in my physics book: There are 2 statements below. Choose a if the second statement is an explanation of the first statement; otherwise, choose b : 1. Ammeter has a very small resistance. 2. The current in the circuit can be said negligibly affected when the ammeter is connected in series with it correctly. I thought the answer should be b , as I thought that statement 1 should be the explanation of statement 2, not vice versa. But the answer said is a . Why?