The diagram illustrates a cross-section of human skin. Which structures are labelled X, Y and Z?
- AX: receptor; Y: sweat gland; Z: hair erector muscle
- BX: receptor; Y: hair erector muscle; Z: sweat gland
- CX: sweat gland; Y: receptor; Z: hair erector muscle
- DX: sweat gland; Y: hair erector muscle; Z: receptor