The correct answer is option 4: 3-1-2-4.

Let`s analyze each option:

Option 1: 4-3-1-2

This option suggests that microwave wavelengths (option 4) are the shortest, followed by ultraviolet (option 3), visible (option 1), and infrared (option 2). However, this is incorrect.

Option 2: 4-1-2-3

This option suggests that microwave wavelengths (option 4) are the shortest, followed by visible (option 1), infrared (option 2), and ultraviolet (option 3). However, this is incorrect.

Option 3: 3-2-1-4

This option suggests that ultraviolet wavelengths (option 3) are the shortest, followed by infrared (option 2), visible (option 1), and microwave (option 4). However, this is incorrect.

Option 4: 3-1-2-4 (Correct answer)

This option suggests that ultraviolet wavelengths (option 3) are the shortest, followed by visible (option 1), infrared (option 2), and finally microwave (option 4). This is the correct sequence.

In conclusion, the