Step 1: Understanding pulley motion.
For belt-driven systems, the length of belt passed over both pulleys must match. Therefore, the linear distance travelled by each pulley is the key to solving the problem.
Step 2: Calculate belt distance for 600 revolutions of the driven pulley.
Driven pulley circumference = 1.2 m.
Revolutions = 600.
\[
\text{Total belt travelled} = 600 \times 1.2 = 720 \text{ m}
\]
Step 3: Find revolutions of driver pulley.
Driver pulley circumference = 40 cm = 0.40 m.
\[
\text{Driver revs} = \frac{720}{0.40} = 1800 \text{ revolutions}
\]
Step 4: Find time at 60 rpm.
\[
\text{Time} = \frac{1800}{60} = 30 \text{ minutes}
\]
Step 5: Conclusion.
Thus, the driver pulley must rotate for 30 minutes, so the correct answer is (B).