Indicate the wrong answer about LeNet neural network from the following options.

Question $4$ options:

The basic units in each convolutional block of LeNet neural network are a convolutional layer, a rectified linear unit $($ReLU$)$ activation function, and a subsequent max$-$pooling operation.

The LeNet neural network was introduced by Yann LeCun, then a researcher at AT&T Bell Labs, for the purpose of recognizing handwritten digits in images.

The basic units in each convolutional block of LeNet neural network are a convolutional layer, a sigmoid activation function, and a subsequent average pooling operation.

Each convolutional layer uses a $5\backslash$times $5$ kernel and a sigmoid activation function.

The LeNet convolutional neural network consists of two parts: $1)$ a convolutional encoder consisting of two convolutional layers; and $2)$ a dense block consisting of three fully$-$connected layers.