In basic radar technology, what is the correct full form of the acronym \"RADAR\"?

Introduction / Context:
Many modern technologies are known by acronyms, and exams often test whether you know the correct expansions. RADAR is a widely used system in aviation, weather forecasting, military applications and traffic control. Knowing its full form helps you remember the basic function of the system, which involves using radio waves to detect and measure the distance of objects.

Given Data / Assumptions:

• The acronym to be expanded is RADAR.
• RADAR uses radio waves to detect objects and measure their range.
• The options provide several similar sounding expansions.
• We need to select the standard and internationally accepted expansion.

Concept / Approach:
The correct full form of RADAR is Radio Detection And Ranging. The word radio indicates the use of radio frequency electromagnetic waves. Detection refers to locating or identifying the presence of objects such as aircraft, ships or rain clouds. Ranging refers to determining the distance or range to the target by measuring the time taken for radio signals to travel to the object and back. Combining these ideas, the name captures the essential function: detecting objects and measuring how far away they are using radio waves.

Step-by-Step Solution:
Step 1: Recall that radar systems transmit radio waves and receive reflected signals from targets.Step 2: The system can detect the presence and sometimes the speed and direction of objects.Step 3: By timing the return of the echo signal, radar determines the distance or range to the object.Step 4: Therefore, the expansion must include words indicating radio, detection and ranging.Step 5: Among the options, Radio Detection and Ranging matches all three core functions.Step 6: Confirm that this is the widely used and correct full form.

Verification / Alternative check:
Reference books, technical documents and standard glossaries in electronics and communication engineering define RADAR as Radio Detection And Ranging. You can also see this expansion in many educational resources and technical dictionaries. The consistency of this expansion across sources verifies that it is the correct one.

Why Other Options Are Wrong:
Region Device and Ranging is not a standard phrase; it does not mention detection and does not clearly relate to radio. Radio Detect and Rangs is grammatically incorrect and uses an incorrect form of range. Radio Device and Ranging again omits the detection aspect that is central to radar systems. None of these alternatives appears in reputable technical literature as the expansion of RADAR.

Common Pitfalls:
Because all the options look similar, candidates may be tricked by small spelling changes or missing words. Some may focus only on the presence of the words radio and ranging and overlook the importance of detection. To avoid such mistakes, remember the logically complete phrase: radio waves are used to detect objects and measure their range, which naturally leads to Radio Detection And Ranging.

Final Answer:
The correct full form of RADAR is Radio Detection and Ranging.