Read the text carefully and fill in the blanks with the correct answer.
The Earth's atmosphere is composed of 5 main layers: the troposphere, the stratosphere, the mesosphere, the thermosphere, and the ________.
The Earth's atmosphere is composed of 5 main layers: the troposphere, the stratosphere, the mesosphere, the thermosphere, and the exosphere.
Complete the following task based on the instruction and optional input provided.### Instruction:
Read the text carefully and fill in the blanks with the correct answer.

### Input:
The Earth's atmosphere is composed of 5 main layers: the troposphere, the stratosphere, the mesosphere, the thermosphere, and the ________.

### Output:
The Earth's atmosphere is composed of 5 main layers: the troposphere, the stratosphere, the mesosphere, the thermosphere, and the exosphere.