PhoCa8ngDihfm7i PhoCa8ngDihfm7i 01-11-2016 Spanish contestada I WOUDNT MIND SOME HELP All multicellular organisms begin as a single cell. Within four or five days, that first cell multiplies into a ball-like structure of about 100 cells. What is this structure called? A. Blastocyst B. Heart C. Placenta D. Blood