The correct option is A ch2 unit2
The perpendicular line from the vertex 'B' to the line AC is called the height of a triangle ABC and it is equal to h.
Since, BC is perpendicular to AC, so AC is the base of a triangle ABC.
Base of the triangle ABC =AC=c
Hence,
Height of the triangle =h unit
Base of the triangle =c unit
As we know,
Area of △ABC=12× Base× Height
=12×c×h
=ch2 unit2