We want to use clustering to transmit a compressed input signal over a network. Our network consists of an encoder and a decoder. The encoder uses pre-computed cluster centroids found with k-means clustering and Euclidean distance to find a representative example of the input signal. The ID of the representative example is then transmitted over the network. Given the cluster centroids:

ID   d1     d2    d3

1    0.5    0.3    0.4

2    0.7    0.8    0.3

3    0.6    0.6    0.5

4    0.2    0.1    0.15

What ID will be transmitted if the input signal is (0.4, 0.4, 0.4)?