The correct answer is option 3 - Serum. Serum is the fluid part of blood that is devoid of corpuscles, which are the cells found in the blood. This means that it does not contain red blood cells, white blood cells, or platelets. Serum is obtained from blood after it has been allowed to clot and the clotting factors have been removed.

Let`s look at the other options for better understanding:

Option 1 - Tissue fluid: Tissue fluid is the fluid that surrounds the cells in our body`s tissues. It is derived from plasma, which is the liquid component of blood, but it is not the correct answer in this case as it is not specifically the fluid part of blood.

Option 2 - Plasma: Plasma is the liquid component of blood that contains various substances such as proteins, ions, hormones, and waste products. While plasma does contain the fluid part of blood, it also contains the corpuscles, so it is not the correct answer in this case.

Option 4 - Lymph: Lymph is a clear fluid that is derived from interstitial fluid, which is the fluid that surrounds the cells in our body`s tissues. It is collected by lymphatic vessels and eventually returns to the blood. Lymph does not specifically refer to