One group of students uses different methods to conserve water as listed below.

Method 1: Close dripping faucets properly and fix leaking ones immediately. Method 2: Use the dishwasher when it is fully loaded.
Method 3: Wash the car with recycled water.
Method 4: Wash hands in a sink half full of water, and do not let the tap run.

Which of these methods does not use any extra water?

a. Method 2 and Method 3
b. Method 1 and Method 3
c. Method 2 and Method 4
d. Method 1 and Method 2