Consider the following systems: Which of these systems can be modelled by the differential equation, a_2 d^2y ( t )dt^2 + a_1 dy ( t )dt + a_0y ( t ) = x ( t )?

Consider the following systems:
Which of these systems can be modelled by the differential equation, $$a_2\frac{d^{2}y\left(t\right)}{d{t}^2}+a_1\frac{dy\left(t\right)}{dt}+a_{0}y\left(t\right)=x\left(t\right)?$$

Answer: Option A