Given that η refers to the learning rate and xᵢ refers to the iᵗʰ input to the neuron, which of the following most suitably describes the weight updation rule of a Kohonen SOM? (where 'j' refers to the jᵗʰ neuron in the lattice)

1. Aw_ij(new) = (1 − η) w_ij(old) + η · x_i
2. Bw_ij(new) = η · w_ij(old) + (1 − η) · x_i
3. Cw_ij(new) = (1 − η) w_ij(old) + x_i
4. Dw_ij(new) = w_ij(old) + η · x_i

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