Okay, let's tackle this question about the telescopic technique in root canal preparation. First, I need to recall what the telescopic technique is. From what I remember, root canal preparation involves shaping the canal to remove infected tissue and prepare it for filling. There are various techniques like step-back, crown-down, balanced force, etc.

The term "telescopic" makes me think of something that involves gradual expansion or a sequence. Maybe it's a stepwise approach where you start from the coronal part and move apically? Wait, the crown-down technique is similar, where you prepare the coronal part first. But the question is about telescopic. Maybe it's a specific method involving multiple instruments in a coordinated way.

I should check my notes. The telescopic technique is also known as the "step-back" technique? No, step-back starts with a larger file size and works down. Wait, maybe the telescopic technique refers to using files in a specific sequence, where each file is inserted a bit deeper than the previous, like telescoping into the canal. That would allow for gradual removal of dentin and shaping. Alternatively, could it be a type of instrumentation technique that uses a series of files to follow each other in a telescoping manner?

Another thought: some techniques use a series of instruments that are inserted in a way that each subsequent file is slightly longer than the previous, creating a telescoping effect. This might help in maintaining the canal's natural curvature and preventing ledges or transportation. The key here is that the telescopic technique is a method of instrumentation where files are used in a specific order, perhaps with a specific sequence of apical to coronal movement or vice versa.

Wait, maybe the correct answer is the step-back technique. Because in step-back, you start with a larger file size and then step back to smaller sizes, but that's more about file size. Alternatively, the crown-down technique is the opposite. But the question is about telescopic. Let me confirm. The telescopic technique is another name for the balanced force technique? No, balanced force is a different method. Hmm.

Alternatively, maybe the telescopic technique is a type of preparation method where the canal is prepared in a stepwise manner, using instruments that are inserted in a telescoping fashion, each one following the previous and extending slightly further. This could be part of the step-back or step-down techniques. Or perhaps it's a specific type of instrumentation technique used in certain systems.

I need to be precise. Let me recall: the step-back technique involves preparing the canal in a stepwise manner, starting from the coronal part and moving apically. Each step is prepared by using a larger file size. The telescopic technique might refer to using instruments in a way that each subsequent file is inserted a bit deeper than the previous, hence "telescoping" into the canal. This would allow for controlled removal of dentin and shaping. So the correct answer would be the step-back technique, which is also known as the telescopic technique. Therefore, the answer is likely the step-back method.

**Core Concept**
The **telescopic technique** refers to a root canal preparation method where successive instruments are inserted in a coordinated sequence, each following the previous one to gradually remove dentin and shape the canal. It emphasizes apical control and sequential coronal enlargement.

**Why the Correct Answer is Right**
The telescopic

✓ Correct Answer: C. Conventional step back