The purpose of the present invention is to avoid ACK / NACK collision in a system in which E-PDCCH control information is transmitted, increase the utilization efficiency of ACK / NACK resources, and suppress unnecessary PUSCH band reduction. A wireless communications terminal having a configuration comprising: a reception unit that receives control signals including ACK / NACK indexes, via an expanded physical downlink control channel; a control unit that determines, on the basis of the ACK / NACK indexes, whether to use a dynamically allocated dynamic ACK / NACK resource or a specified resource specified beforehand, to send downlink data ACK / NACK signals; and a transmission unit that sends the ACK / NACK signals using the dynamic ACK / NACK resource or the specified resource, as determined.