A communications apparatus, comprising a communications unit and a processing unit, wherein the communications unit is configured to receive X physical sidelink shared channels PSSCHs from at least one sending terminal, wherein one PSSCH corresponds to one physical sidelink feedback channel PSFCH resource, X PSFCH resources corresponding to the X PSSCHs have a same time domain resource, and X is an integer greater than 1; the processing unit is configured to determine M PSFCH resources based on priorities of the X PSFCH resources, transmit power corresponding to the X PSFCH resources, and total transmit power of the apparatus, wherein M is less than or equal to M', and M' is an upper limit of a quantity of PSFCH resources occupied on a same time domain resource, and wherein the processing unit is configured to sequentially accumulate, in descending order of the priorities of the X PSFCH resources, the transmit power corresponding to the PSFCH resources, and determine the M PSFCH resources based on the accumulation, wherein the X PSFCH resources are classified into L priorities, wherein a quantity of PSFCH resources with an i th priority in the L priorities is denoted as li, and a smaller value of i indicates a higher priority, wherein the transmit power corresponding to the PSFCH resources is accumulated in descending order of the priorities of the X PSFCH resources, and an accumulation result is expressed as ∑ j = 1 k P j, wherein P j represents transmit power corresponding to a j th PSFCH resource sorted in descending order of the priorities, j is an integer greater than 0, and k is a quantity of accumulated PSFCH resources; and the communications unit is further configured to send feedback information to some or all of the at least one sending terminal on the M PSFCH resources. the communications unit is configured to receive X physical sidelink shared channels PSSCHs from at least one sending terminal, wherein one PSSCH corresponds to one physical sidelink feedback channel PSFCH resource, X PSFCH resources corresponding to the X PSSCHs have a same time domain resource, and X is an integer greater than 1; the processing unit is configured to determine M PSFCH resources based on priorities of the X PSFCH resources, transmit power corresponding to the X PSFCH resources, and total transmit power of the apparatus, wherein M is less than or equal to M', and M' is an upper limit of a quantity of PSFCH resources occupied on a same time domain resource, and wherein the processing unit is configured to sequentially accumulate, in descending order of the priorities of the X PSFCH resources, the transmit power corresponding to the PSFCH resources, and determine the M PSFCH resources based on the accumulation, wherein the X PSFCH resources are classified into L priorities, wherein a quantity of PSFCH resources with an i th priority in the L priorities is denoted as li, and a smaller value of i indicates a higher priority, wherein the transmit power corresponding to the PSFCH resources is accumulated in descending order of the priorities of the X PSFCH resources, and an accumulation result is expressed as ∑ j = 1 k P j, wherein P j represents transmit power corresponding to a j th PSFCH resource sorted in descending order of the priorities, j is an integer greater than 0, and k is a quantity of accumulated PSFCH resources; and the communications unit is further configured to send feedback information to some or all of the at least one sending terminal on the M PSFCH resources.