53. Some sites use a software to update their web content or indices of others sites' web content. This is ..........software. A) Web crawling B) Spidering C) Learning D) A or B E) All 54. Termination criteria for gradient descent algorithm may be A) Patterns termination B) No. of iterations C) Error D) B or C E) All 55. Understanding gene data can be reached by applying ..... A) KNN B) k-means C) Clustering learning algorithm. D) B or C E) All 56. K-means algorithm is based on ..... ...... to terminate learning process. A) Patterns termination B) Error C) No. of iterations D) A or C E) All 57. Gradient of a continuous and differentiable function: A) Decreases as you get closer B) Is non-zero to the minimum at a maximum C) Is zero at a saddle point D) Is zero at E) A,C,D a minimum