The correct option is A Ostrich egg
The largest biological cell is the ostrich egg, which is about 6 inches (15 cm) long and weighs about 3 pounds (1.4 kg). The smallest known living cell is the mycoplasma bacterium. The ostrich egg is about 5000 times bigger than the Mycoplasma. The cells are a type of bacteria and only grow to be 0.8 micrometres. The smallest cell in the human body is the sperm cell but they are not the smallest.