In direct form for realisation of IIR filters,1) Denominator coefficients are the multipliers in the feed forward paths2) Multipliers in the feedback paths are the positives of the denominator coefficients3) Numerator coefficients are the multipliers in the feed forward paths4) Multipliers in the feedback paths are the negatives of the denominator coefficients

• A. 1, 2 and 3 are correct
• B. 1 and 2 are correct
• C. 3 and 4 are correct
• D. All the four are correct