Many people consider neural networks as potentially intelligent, or even comparable to human minds. Among the following statements, what is one reason one might question this idea?

a$.$ An AI network operates exclusively on words, and in this sense arguably does not comprehend sentences.

b$.$ An AI network is electrically inefficient.

c$.$ Thus far, outcomes of AI networks have not produced linguistic results similar to human beings.

d$.$ The AI networks operative in language systems $($such as ChatGPT$)$ are only capable of one skill.