The correct answer is A) it will change from blue to green. When a halide torch is used to detect a refrigerant leak, the flame will change color as the exploring tube approaches the leak. Refrigerants like Freon contain halogen compounds, which will cause the flame to change from its normal blue color to a distinct green color when the exploring tube gets close to the leak. This color change is a clear indicator that a refrigerant leak has been detected. The other answer choices are incorrect because the flame would not change to orange (C) or stay blue (D), as those do not match the typical color change observed when a halide torch detects a refrigerant leak. Option B, changing from green to blue, is also incorrect as the normal flame color is blue, which then changes to green when the leak is detected.