Final answer:
The correct term for the condition involving excessive secretion of sebum is 'Seborrhea' (C). This condition relates to the overactivity of sebaceous glands, which produce sebum to lubricate the skin and hair.
Step-by-step explanation:
The proper spelling for the term that means pertaining to the excessive secretion of sebum is C) Seborrhea. Seborrhea involves the overactivity of the sebaceous glands, which are oil glands in the dermis layer of the skin responsible for producing sebum. This substance is vital for lubricating and waterproofing both the hair and skin, as well as for providing antibacterial properties that help protect the skin from microbial growth. The condition of seborrhea is often associated with hormonal changes and typically becomes noticeable after puberty when these glands become more active.