The correct option is 3.
Enzymes are biological catalysts which speed up the rate of biochemical reactions inside the cells. Enzymes are very specific in action and they require specific conditions called optimum conditions for them to function optimally.
When the optimum conditions are not met, an enzyme's activity will be lowered or totally stopped.
Conditions that affect the optimum activity of an enzyme include: temperature, pH level and regulatory activity of regulatory enzymes and hormones.
It’s someone’s opinion so the key word “best hints that it an opinion so to be objective is to be unbiased. If you're objective about something, you have no personal feelings about it.
All the cells in a person's body have the same DNA and the same genes. However, the difference between cells in different tissues and organs is that the "expression" of the genes differs between cells. Expression means that the message from the DNA is being copied and made into protein.
The right answer for the question that is being asked and shown above is that:
The density of a certain object can be solved using two parameters: The mass and the volume.
Density = mass / volume.
So, from the given question, we are lacking on what the volume is.