Step 1: Focus on the two key requirements in the question.
We need an instrument that measures roof to floor convergence specifically, and it must allow reading from a remote location rather than requiring someone to stand right at the measurement point.
Step 2: Rule out instruments that measure the wrong quantity.
Extensometers, whether tell tale or magnetic ring multipoint types, are borehole instruments that track movement inside the rock mass at different depths, they do not directly give the total roof to floor convergence, and load cells measure force or pressure on supports, not displacement at all.
Step 3: Focus on the device that matches both requirements.
A convergence recorder is fixed between the roof and floor and senses the closing distance between them, when this sensor is wired to send its reading to a display unit placed safely away from the working area, it becomes a remote convergence recorder, letting engineers monitor roof floor closure continuously without staying in a risky zone.
Step 4: Conclude.
So the instrument fitting both the convergence measurement and remote reading requirement is the remote convergence recorder.
\[ \boxed{\text{Remote convergence recorder}} \]