Classify the following emotion as happy, angry, sad, or surprised.
The children were excited as they watched the fireworks.
The emotion in this sentence can be classified as happy.
Complete the following task based on the instruction and optional input provided.### Instruction:
Classify the following emotion as happy, angry, sad, or surprised.

### Input:
The children were excited as they watched the fireworks.

### Output:
The emotion in this sentence can be classified as happy.