Answer:
c. Weight is input, height is output
Explanation:
It is given here that "Height is a function of Weight".
which means

Thus, value of Height is depend on the value of Weight.
Thus, Weight is input variable and Height is output variable.
Hence option (c) is correct.
Further,
The variable that we can change is called the Input variable.
The Output variable depends upon the input variable, as we change the value of the input variable the value of the output variable is also get changed.