Right answer is (c) Feeding in continuous stream
The best I can explain: The feeder is a slow speed rotating drum on which large numbers of small blades are mounted. It supplies coal to the spreaders in continuous stream. The speed of the feeder can be adjusted as per the load on plant. The feeders are operated with variable speed drive to control the combustion as per the requirement. The feeders may be reciprocating ram, endless belt or spiral worm.