Choose the word which can be substituted for the given words/sentence:
Through which light cannot pass
A) Dull
B) Dark
C) Obscure
D) Opaque

Hint:Substitute here indicate the synonym for the words or sentence. Synonyms are the words that have the same or similar meaning and those words can be substituted or can be used in place of each other.

Complete answer:
We must find one word for the sentence ‘Through which light cannot pass’ and the meaning of words that are given in the options.
The meaning of the sentence ‘Through which light cannot pass’ is not able to see through or not transparent. And we must find the correct answer from the options that can substitute the given sentence in one word.

Option A) Dull – is an incorrect answer because the meaning of dull is ‘lacking interest or excitement or uninteresting’ and the word dull cannot be substituted for the sentence Through which light cannot pass. Thus, this is an incorrect answer.

Option B) Dark - is an incorrect answer because the meaning of dark is ‘with little or no light or dark’ and the word dark cannot be substituted for the sentence Through which light cannot pass. Thus, this is an incorrect answer.

Option C) Obscure - is an incorrect answer because the meaning of obscure is ‘not discovered or known about; uncertain or unknown’ and the word obscure cannot be substituted for the sentence Through which light cannot pass. Thus, this is an incorrect answer.

Option D) Opaque – is the right answer because the meaning of opaque is ‘not able to be seen through; not transparent or cloudy or blurred or hazy’ and this word is the correct substitute for the sentence ‘Through which light cannot pass’. Thus, this is the correct answer.

Hence, the correct answer is Option ‘D’.

Note: Substitute means something can be used in place of each other. Like the sentence ‘Through which light cannot pass’ has a substitute word and that is opaque. So, this is the correct word: rest does not give the substitute word the given sentence. So, option D is the most suitable answer.