The heat generated in a circuit is given by `Q = I^(2) Rt` , where `I` is current , `R` is resistance , and `t` is time . If the percentage errors in measuring `I , R , and t are 2% , 1% , and 1%` , respectively , then the maximum error in measuring heat will be
A. `2%`
B. `4%`
C. `6%`
D. `8%`