Answer: Fourth option is correct.
Step-by-step explanation:
Independent variables are those variables in which two events are occurred irrespective of one another.
The occurrence of one event does not affect the another event.
According to options :
a person’s income and savings is dependent variables because savings of any individual is completely dependent upon his income.
Price of a car is dependent upon the price of steel which it is made up of.
Price of vegetable soup is dependent upon the price of vegetables.
Price of cell phone is not dependent upon the price of a penthouse.
So, they are independent variables.
Hence, Fourth option is correct.