[单选题]
A 200-L electric water heater uses 2 zolxa;e -+v.v kqs; 7 yib9ly.qW. Assuming no heat loss, how long would it take to heat water s97; li.yqyqb in this tank from $23 \; ^{\circ}C$ to $75 \; ^{\circ}C$?
A. $5 \; hours$
B. $6 \; hours$
C. $7 \; hours$
D. $8 \; hours$
