Consider the following statements about Global Positioning Systems (GPS):1) The position of an object can be exactly determined by a single satellite2) The position of the observer (moving person or vehicle) on the ground is determined by an orbiting satellite3) Atomic clocks are fixed in satellites to calculate the positioning of the satellite to aid in determining travel times.4) Absolute positioning, where an accuracy of 1 cm to 5 cm is needed, depends upon the health of the satelliteWhich of the above statements are correct?

• A. 1, 2 and 3 only
• B. 1, 2 and 4 only
• C. 1, 3 and 4 only
• D. 2, 3 and 4 only