The sentence below has four parts (A, B, C, and D). One part has a grammatical error. Identify the part.
Modern political praxis (A)/ is thoroughly now (B)/ permeated with (C)/ a productivist ethos. (D)

Correct option is B

Option (b) contains a grammatical error.
Explanation:
The adverb "now" should come before or after the auxiliary verb, not in the middle of "is thoroughly now".
Correct phrasing: "is now thoroughly permeated" or "is thoroughly permeated now"
The phrase "is thoroughly now permeated" is ungrammatical in standard English.
Correct sentence:
Modern political praxis is now thoroughly permeated with a productivist ethos.
Grammatical rule used:
Adverbs of time (now, then) are typically placed before the main verb but after the auxiliary verb in a sentence.
Example:
· Incorrect: He is always late now.
· Correct: He is now always late.