Question 71 Interstitial fluid: A Contains antibodies produced by white blood cells B Contains red and white blood cells C is found in the spaces between cells and becomes lymph when it enters lymph capillaries D Is present in connective tissue E Contains blood-clotting factors

The correct answer is:<br /><br />**(C) Is found in the spaces between cells and becomes lymph when it enters lymph capillaries**<br /><br />### Explanation:<br />Interstitial fluid is the fluid that surrounds and bathes the cells in tissues. It is derived from blood plasma and serves as a medium for the exchange of nutrients, gases, and waste products between blood and cells. Here’s why the other options are incorrect or less accurate:<br /><br />- **(A) Contains antibodies produced by white blood cells**: While interstitial fluid may contain some antibodies, this is not its primary characteristic. Antibodies are more commonly associated with blood plasma and lymph.<br /><br />- **(B) Contains red and white blood cells**: Interstitial fluid does not typically contain red blood cells. White blood cells may occasionally migrate into the interstitial space during immune responses, but this is not a defining feature of interstitial fluid.<br /><br />- **(D) Is present in connective tissue**: While interstitial fluid is present in all tissues, including connective tissue, this statement is too general and does not specifically define interstitial fluid.<br /><br />- **(E) Contains blood-clotting factors**: Blood-clotting factors are primarily found in blood plasma, not in interstitial fluid.<br /><br />Thus, the most accurate description of interstitial fluid is that it is found in the spaces between cells and becomes lymph when it enters lymph capillaries.