A resistance R is to be measured using a meter bridge. Student chooses the standared resistance S to be `100 Omega`. He finds the null point at `l_(1)=2.9cm`. He is told to attempt to improve the accuracy. Which of the folllowing is a useful way?
A. He should measure `l_(1)` more accurately
B. He should change S to `1000Omega` and repeat the experiment
C. He should change S to 3`Omega` and repeat the experiment
D. He should given up hope of a more accurate measurement with a meter bridge
