**Homogeneous Differential Equation**

A homogeneous differential equation is a type of differential equation in which all terms can be expressed as a linear combination of the dependent variable and its derivatives. In other words, if we have a differential equation of the form:

\[a_0(x)y^{(n)}(x) + a_1(x)y^{(n-1)}(x) + \ldots + a_{n-1}(x)y'(x) + a_n(x)y(x) = 0\]

where \(y^{(n)}(x)\) represents the nth derivative of the dependent variable \(y(x)\), and \(a_0(x), a_1(x), \ldots, a_n(x)\) are functions of \(x\), then this equation is said to be homogeneous.

**Forcing Function**

The forcing function, also known as the non-homogeneous term, is a term that is added to the homogeneous differential equation to account for external influences or forces acting on the system. It represents an input or stimulus that affects the behavior of the system.

In the context of the given question, the differential equation is said to be homogeneous. This means that the equation does not have any non-homogeneous terms or forcing functions. In other words, the equation does not include any external influences or forces.

**Value of the Forcing Function**

Since the differential equation is homogeneous, the value of the forcing function is zero. This is because there are no external influences or forces acting on the system. The equation only describes the behavior of the system based on its internal properties.

Therefore, the correct answer to the question is (a) 0, indicating that the value of the forcing function is zero for a homogeneous differential equation.

The homgenuos eq of form (dy/dx)+py=0. So the forcing fn is zero