A wheatstone bridge is used to determine the value of unknown resistance $X$ by adjusting the variable resistance $Y$ as shown in the figure. For the most precise measurement of $X$, the resistances $P$ and $Q$:
  • A
    should be approximately equal and are small
  • B
     should be very large and unequal
  • C
    do not play any significant role
  • D should be approximately equal to $2 X$
NEET 2022, Medium
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