[amp_mcq option1=”T/66 A” option2=”T/66 C” option3=”T/66 B” option4=”T/66″ correct=”option1″]
The correct answer is A. T/66 A.
A train signal register is a device that records the passage of trains along a railway line. It consists of a number of track circuits, each of which detects the presence or absence of a train. The track circuits are connected to a central controller, which records the number of trains that have passed each track circuit.
The number of train signal registers required for a double line is two, one for each track. This is because each track must be able to be operated independently of the other. If there was only one train signal register, it would not be possible to operate both tracks at the same time.
The T/66 A is a type of train signal register that is commonly used in the United States. It is a reliable and accurate device that is well-suited for use in railway applications.
The other options are incorrect because they do not represent the correct number of train signal registers required for a double line.