If a body is rotating about an axis, passing through its centre of mass then its angular momentum is directed along its:

CONCEPT:

Angular Momentum

• It is the property of a rotating body and it is defined as the product of the moment of inertia and the angular velocity of the rotating object.
• It is a vector quantity

​\(\Rightarrow \vec{L}=I\times\vec{\omega}\)     

where I = moment of inertia and ω = angular velocity

EXPLANATION:

• Mathematically, the angular momentum is written as

\(\Rightarrow \vec{L}=I\times\vec{\omega}\)     -----(1)

• Since the angular velocity acts along the axis of rotation, so by equation 1 it is clear that the angular momentum will also act along the axis of rotation.
• Hence, option 3 is correct.