Which of the following statements are true? 1. Mechanical comparators are compact and easy to handle 2. Parallax error is never observed in mechanical comparator 3. Sigma comparator is a type of mechanical comparator 4. Mechanical comparators have low inertia which makes them sensitive to vibrations

• A. 1 and 2
• B. 3 and 4
• C. 1 and 3
• D. All of the above