Step 1: Energy Conservation
Mechanical energy (Potential Energy) is converted into heat to melt ice: $mgh = m_{ice}L$.
Step 2: Potential Energy
$P.E. = 3.5 \times 10 \times 2000 = 70,000 \text{ J}$
Step 3: Melting Calculation
$70,000 = m_{ice} \times (3.5 \times 10^5)$
$m_{ice} = \frac{70,000}{350,000} = \frac{7}{35} = 0.2 \text{ kg}$
Step 4: Unit Conversion
$0.2 \text{ kg} = 200 \text{ grams}$
Final Answer:(C)