Among the following sets of salient features, which set does not exclusively characterize mammals?

• A. Presence of sweat, glands, hairs on skin and diphyoclonts
• B. Presence of mammary glands, sweat glands and diaphragm
• C. Presence of mammary' glands, sweat glands, and diaphragm
• D. Presence of mammary glands, hairs on skin and diaphragm.