The induced emf can be produced in a coil by A. moving the coil with uniform speed inside uniform magnetic…

Induced emf is given by Faraday's law

$\left|\epsilon \right|=\frac{d\varphi }{dt}$

where $\varphi$ is the magnetic flux.

The rate of change of flux through a circuit is defined as emf. The formula for flux is $\varphi =\overrightarrow{B}·\overrightarrow{A}$. In the statements $A\&B$ given in the question, the magnetic flux in the coil in uniform magnetic field does not change. So, no emf is induced.

But in statement $C$, the angle between the area vector and the magnetic field continuously changes hence, an emf is generated. In statement $D$, the area is changing in unit time so magnetic flux will change and an emf is generated.