Select the option that can be used as a one-word substitute for given group of words.
Unable to speak distinctly or express oneself clearly

Correct option is D

The correct one-word for the given group of words is (d) Inarticulate.
Inarticulate: Unable to express one's thoughts or speech clearly. (अस्पष्ट भाषी / स्पष्ट रूप से न बोल पाने वाला)
Example: His nervousness made him appear inarticulate during the interview.
Meanings of the given other options:
· (a) Inane: Silly or stupid (मूर्खतापूर्ण)
· (b) Inapt: Not suitable or appropriate (अप्रासंगिक)
· (c) Inarch: Not a valid standard word; possibly miswritten or nonexistent.