For the circuit diagram shown, a battery with negligible internal resistance is joined in series with two fixed resistors $R_1$ and $R_2$. This circuit will be used to check whether the electromotive force (e.m.f.) of a certain cell is $1.5\,\text{V}$. The cell is placed between terminals $X$ and $Y$, in parallel with $R_2$, and in series with a galvanometer. Which statement about this test is correct?
- AAny non-zero reading on the galvanometer means the cell has an e.m.f. of $1.5\,\text{V}$.
- BThe battery does not need to have an e.m.f. of $6.0\,\text{V}$.
- CThe cell may be connected either way round between $X$ and $Y$.
- DThe galvanometer does not need a scale calibrated in amperes.