Water Content in Blood: Entering vs. Leaving the Kidneys

The answer is: entering

The kidneys are responsible for filtering waste products from the blood and producing urine. As blood enters the kidneys, it is filtered through a series of structures called nephrons. The nephrons remove waste products and excess water from the blood, which is then sent back into the body. The urine, which contains the filtered waste products, is then sent to the bladder and eventually excreted from the body. Therefore, the blood entering the kidneys contains more water than the blood leaving it.