Which neural network is used in the face recognition case?

Which optimizer is used in the following code?
Adadelta = tf.keras.optimizers.Adadelta ()
Model.compile （loss=' binary_crossentropy ',
Optimizer = ' adam ',
Metrics = ['accuracy'])

Which of the following is not a NLP language feature?

Natural language processing can be defined as a discipline that studies language problems in human-to-human communication and human-to-computer communication. Natural language processing requires the development of models that represent language ability and language application, the establishment of a computational framework to implement such language models, the proposal of corresponding methods to continuously improve such language models, the design of various practical systems based on such language models, and the discussion of the evaluation techniques of these practical systems.

The core problem of computer vision ()