Differential Equations

Which of the following first-order differential equations are LINEAR in $y$?

Options:

• (A) $\frac{dy}{dx} + 5y = \sin x$
• (B) $x \frac{dy}{dx} + 2y = e^x$
• (C) $\frac{dy}{dx} + y^2 = x$
• (D) $\frac{dy}{dx} + x y = x^3$