Accumulation of waste products from protein metabolism is the primary cause of uremia. ___________ must be restricted in CRF clients, however, if intake is inadequate, a negative nitrogen balance occurs, causing muscle wasting. The ________ is most often used as an indicator for levels of protein consumption.

a) Fats; Blood urea nitrogen (BUN)
b) Carbohydrates; Serum creatinine
c) Proteins; Blood glucose
d) Fiber; Serum albumin