Correct Option: B

Blood is considered a connective tissue for two basic reasons:
(1) it has the same origin as do the other connective tissue types and
(2) blood connects the body systems together bringing the needed oxygen, nutrients, hormones and other signaling molecules, and removing the wastes. In circulating blood two different cell types are found: enucleated erythrocytes or red blood cells and nucleated leukocytes or white blood cells.