The G-protein couples receptors are among the most diverse group of the membrane protein receptors. The GPCRs attaches a wide variety of the signalling molecules. They interact with the G proteins which are present in the membrane. Conformational changes occur in the GPCR, when the external signalling molecules attaches to it. The GPCR is desensitized after it becomes activated.
Hence, the answer is 'Option D - desensitized'.