1. A method for transmitting uplink control information by a user equipment in a wireless communication system supporting carrier aggregation of a plurality of cells containing a first cell and a second cell, the method comprising:receiving a random access response via a physical downlink shared channel (PDSCH) from a base station,
wherein the random access response schedules a first physical uplink shared channel (PUSCH) transmission on the first cell;
receiving downlink control information via a physical downlink control channel (PDCCH) from the base station,
wherein the downlink control information schedules a second PUSCH transmission on the second cell; and
when the first PUSCH transmission and the second PUSCH transmission are configured in a same subframe, transmitting the uplink control information to the base station on the second cell via the second PUSCH,
wherein the first PUSCH transmission scheduled on the first cell is dropped.