I want to say A. or C.
They seem the most realistic..
The best way to describe a human sperm cell is a tad pole (Baby frog). Like the sperm cell the tad pole has a head, body and a tail. Though tad poles are finished products, the sperm cell needs to combine with the egg cell for it to be fertilized.
It resting heart rate will decrease after being conditioned by physical exercise
The reason that you can tell that it was chemical is because you can see the bubbles forming. This means that it is giving off a gas.
B. is the answer. hope that helps. :)
