Final answer:
The statement is false (b) because the resistance is greater in narrower tubes, which leads to a larger pressure drop for a given flow rate. While capillary action is affected by the tube diameter, it is different from pressure drop during fluid flow.
Step-by-step explanation:
The statement 'The smaller the diameter of the capillary tube, the smaller the pressure drop' is false(b). According to the principles of fluid dynamics and the equation P₂ - P₁ = RQ, where P represents pressure, R represents resistance, and Q represents flow rate, the resistance is greater in narrower tubes. For a given flow rate, the pressure drop across a narrow section of a tube will be greater than that across a wider section. This is due to higher resistance causing more pressure to be lost as the fluid flows through.
Capillary action is another phenomenon that can be affected by the diameter of a tube. However, this relates to the height a fluid can rise due to surface tension and adhesion, which is different from pressure drop due to flow resistance. As the diameter of a tube decreases, the capillary action will cause the fluid to rise higher, but this does not mean there is a smaller pressure drop during flow through the tube.
Considering the behavior of blood flow in the human body, as arteries become narrower, the resistance to blood flow through them increases due to the friction of the blood against the arterial walls, leading to a reduction in blood pressure before blood enters the capillaries. This mechanism is crucial for preventing damage to the delicate capillary network.