Which wave has the smallest amplitude?

Answer:
C. C
Explanation:
A wave can be defined as a disturbance in a medium that progressively transports energy from a source location to another location without the transportation of matter.
In Science, there are two (2) types of wave and these include;
I. Electromagnetic waves: it doesn't require a medium for its propagation and as such can travel through an empty space or vacuum. An example of an electromagnetic wave is light.
II. Mechanical waves: it requires a medium for its propagation and as such can't travel through an empty space or vacuum. An example of a mechanical wave is sound.
A crest can be defined as the highest (vertically) point on a waveform.
On a related note, a trough is the lowest (vertically) on a waveform.
An amplitude can be defined as a waveform that's measured from the center line (its origin or equilibrium position) to the bottom of a trough or top of a crest. Thus, the vertical axis (y-axis) is the amplitude of a waveform i.e it's measured vertically.
In this scenario, waveform C which is represented by a blue curvy line has the smallest amplitude in comparison with the other waveforms because it has the minimum height when measured from the origin.
In contrast, waveform A represented by a purple line has the highest amplitude because it has the maximum height when measured from the origin.
Mathematically, the amplitude of a wave is given by the formula;
x = Asin(ωt + ϕ)
Where;
Answer:
The answer is indeed D as the comment above suggests.
Explanation:
Simply put, wave D's highest point is closer to the line than all of the other high points of A, B and C